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TclX(TCL)                                                                                          TclX(TCL)



NAME
       TclX - Extended Tcl: Extended command set for Tcl

SYNOPSIS
       package require Tclx


INTRODUCTION
       This  man page contains the documentation for all of the extensions that are added to Tcl by Extended
       Tcl (TclX).  TclX extends Tcl's capabilities by adding new commands to it, without changing the  syn-tax syntax
       tax  of standard Tcl.  Extended Tcl is a superset of standard Tcl and is built alongside the standard
       Tcl sources.

       Extended Tcl was created by Karl Lehenbauer and Mark Diekhans and is freely redistributable  for  any
       use without license or fee.

       Available  since  1989,  Extended Tcl, also known as TclX, not only adds capabilities to Tcl, but has
       also been the source of many of the capabilities of  the  baseline  Tcl  release,  including  arrays,
       files, sockets, file events, and date and time handling, among others.

       Extended Tcl introduces a set of new commands and a user-extensible library of useful Tcl procedures,
       any of which can be automatically loaded on the first attempt to execute it.

       The command descriptions are separated into several sections:

             General Commands

             Debugging and Development Commands

             Unix Access Commands

             File Commands

             Network Programming Support

             File Scanning Commands

             Math Commands

             List Manipulation Commands

             Keyed Lists

             String and Character Manipulation Commands

             XPG/3 Message Catalog Commands

             Help Facility

             Tcl Loadable Libraries and Packages

GENERAL COMMANDS
       A set of general, useful Tcl commands, includes a command to begin an interactive session with Tcl, a
       facility for tracing execution, and a looping command.

       dirs   This procedure lists the directories in the directory stack.

       commandloop ?-async? ?-interactive on | off | tty? ?-prompt1 cmd? ?-prompt2 cmd? ?-endcommand cmd?

              Create  an interactive command loop reading commands from stdin and writing results to stdout.
              Command loops are maybe either be blocking or event oriented.  This command is useful for  Tcl
              scripts  that  do not normally converse interactively with a user through a Tcl command inter-preter, interpreter,
              preter, but which sometimes want to enter this mode, perhaps for debugging or user  configura-tion. configuration.
              tion.  The command loop terminates on EOF.

              The following options are available:

              -async A  command handler will be associated with stdin.  When input is available on stdin, it
                     will be read and accumulated until a full command is available.  That command will then
                     be evaluated.  An event loop must be entered for input to be read and processed.

              -interactive on | off | tty
                     Enable or disable interactive command mode.  In interactive mode, commands are prompted
                     for and the results of comments are printed.  The value maybe any boolean value or tty.
                     If  tty  is used, interactive mode is enabled if stdin is associated with a terminal or
                     terminal emulator.  The default is tty.

              -prompt1 cmd
                     If specified, cmd  is used is evaluate and its result used for the main command prompt.
                     If  not  specified, the command in tcl_prompt1 is evaluated to output the prompt.  Note
                     the difference in behavior, cmd results is used, while tcl_prompt1 outputs.  This is to
                     allow for future expansion to command loops that write to other than stdout.

              -prompt2 cmd
                     If  specified, cmd is used is evaluate and its result used for the secondary (continua-tion) (continuation)
                     tion) command prompt.  If not specified, the command in  tcl_prompt2  is  evaluated  to
                     output the prompt.

              -endcommand cmd
                     If specified, cmd is evaluated when the command loop terminates.

                     In interactive mode, the results of set commands with two arguments are not printed.

                     If  SIGINT  is configured to generate a Tcl error, it can be used to delete the current
                     command being type without aborting the program in progress.

       echo ?str ...?
              Writes zero or more strings to standard output, followed by a newline.

       infox option

              Return information about Extended Tcl, or the current application.  The following  infox  com-mand command
              mand options are available:

              version
                     Return the version number of Extended Tcl.  The version number for Extended Tcl is gen-erated generated
                     erated by combining the base version of the standard Tcl code with another number indi-cating indicating
                     cating the version of Extended Tcl being used.

              patchlevel
                     Return the patchlevel for Extended Tcl.

              have_fchown
                     Return  1  if the fchown system call is available.  This supports the -fileid option on
                     the chown and chgrp commands.

              have_fchmod
                     Return 1 if the fchmod system call is available.  This supports the -fileid  option  on
                     the chmod command.

              have_flock
                     Return 1 if the flock command defined,  0 if it is not available.

              have_fsync
                     Return  1 if the fsync system call is available and the sync command will sync individ-ual individual
                     ual files.  0 if it is not available and the sync command will  always  sync  all  file
                     buffers.

              have_ftruncate
                     Return  1 if the ftruncate or chsize system call is available.  If it is, the ftruncate
                     command -fileid option maybe used.

              have_msgcats
                     Return 1 if XPG message catalogs are available, 0 if they  are  not.   The  catgets  is
                     designed to continue to function without message catalogs, always returning the default
                     string.

              have_posix_signals
                     Return 1 if Posix signals are available (block and unblock options  available  for  the
                     signal command).  0 is returned if Posix signals are not available.

              have_signal_restart
                     Return 1 if restartable signals are available (-restart option available for the signal
                     command).  0 is returned if restartable signals are not available.

              have_truncate
                     Return 1 if the truncate system call is available.  If it is, the ftruncate command may
                     truncate by file path.

              have_waitpid
                     Return  1  if  the waitpid system call is available and the wait command has full func-tionality. functionality.
                     tionality.  0 if the wait command has limited functionality.

              appname
                     Return the symbolic application  name  of  the  current  application  linked  with  the
                     Extended  Tcl  library.   The  C  variable tclAppName must be set by the application to
                     return an application specific value for this variable.

              applongname
                     Return a natural language name for the current application. The C variable  tclLongApp-Name tclLongAppName
                     Name  must  be  set by the application to return an application specific value for this
                     variable.

              appversion
                     Return the version number for the current application.  The  C  variable  tclAppVersion
                     must  be  set by the application to return an application-specific value for this vari-able. variable.
                     able.

              apppatchlevel
                     Return the patchlevel for the current application.   The  C  variable  tclAppPatchlevel
                     must  be  set by the application to return an application-specific value for this vari-able. variable.
                     able.

       for_array_keys var array_name code
              This procedure performs a foreach-style loop for each key in the named array.  The  break  and
              continue statements work as with foreach.

       for_recursive_glob var dirlist globlist code
              This  procedure performs a foreach-style loop over recursively matched files.  All directories
              in dirlist are recursively searched (breadth-first), comparing each  file  found  against  the
              file  glob  patterns  in globlist.  For each matched file, the variable var is set to the file
              path and code is evaluated.  Symbolic links are not followed.

       loop var first limit ?increment? body
              Loop is a looping command, similar in behavior to the Tcl for statement, except that the  loop
              statement  achieves  substantially higher performance and is easier to code when the beginning
              and ending values of a loop are known, and the loop variable is to be incremented by a  known,
              fixed amount every time through the loop.

               The  var  argument  is the name of a Tcl variable that will contain the loop index.  The loop
              index is set to the value specified by first.  The Tcl interpreter is invoked upon  body  zero
              or more times, where var is incremented by increment every time through the loop, or by one if
              increment is not specified.  Increment can be negative in which case the loop will count down-wards. downwards.
              wards.

              When  var  reaches  limit,  the  loop  terminates without a subsequent execution of body.  For
              instance, if the original loop parameters would cause loop to terminate, say  first  was  one,
              limit  was  zero  and increment was not specified or was non-negative, body is not executed at
              all and loop returns.

              The first, limit and increment are integer expressions.  They are only evaluated once  at  the
              beginning of the loop.

              If a continue command is invoked within body then any remaining commands in the current execu-tion execution
              tion of body are skipped, as in the for command.  If a break command is  invoked  within  body
              then the loop command will return immediately.  Loop returns an empty string.

       popd   This  procedure  pops the top directory entry from the directory stack and make it the current
              directory.

       pushd ?dir?
              This procedure pushes the current directory onto the directory stack and cd to  the  specified
              directory.   If  the  directory  is  not  specified, then the current directory is pushed, but
              remains unchanged.

       recursive_glob dirlist globlist
              This procedure returns a list of recursively matches files.  All directories  in  dirlist  are
              recursively searched (breadth-first), comparing each file found against the file glob patterns
              in globlist.  Symbolic links are not followed.

       showproc ?procname ...?
              This procedure lists the definition of the named  procedures.   Loading  them  if  it  is  not
              already  loaded.   If no procedure names are supplied, the definitions of all currently loaded
              procedures are returned.

       try_eval code catch ?finally?
              The try_eval command evaluates code in the current context.

       If an error occurs during the evaluation and catch is not empty, then catch is evaluated  to  handler
       the error.  The result of the command, containing the error message, will be stored in a global vari-able variable
       able errorResult.  The global variables errorResult, errorInfo and errorCode will  be  imported  into
       the  current  scope,  there  is no need to execute a global command.  The result of the catch command
       becomes the result of the try_eval command.  If the error that caused the catch to be evaluate is  to
       be continued, the following command should be used:
            error $errorResult $errorCode $errorInfo

       If  the  finally argument is supplied and not empty, it is evaluated after the evaluation of the code
       and the catch commands.  If an error occurs during the evaluation of the finally command, it  becomes
       the  result of the try_eval command.  Otherwise, the result of either code  or catch is preserved, as
       described above.

DEBUGGING AND DEVELOPMENT COMMANDS
       This section contains information on commands and procedures  that  are  useful  for  developing  and
       debugging Tcl scripts.


       cmdtrace level | on ?noeval? ?notruncate? ?procs? ?fileid? ?command cmd?

              Print  a  trace  statement  for all commands executed at depth of level or below (1 is the top
              level).  If on is specified, all commands at any level are traced.  The following options  are
              available:

              noeval Causes  arguments to be printed unevaluated.  If noeval is specified, the arguments are
                     printed before evaluation.  Otherwise, they are printed afterwards.

                     If the command line is longer than 60 characters, it is truncated to 60 and a "..."  is
                     postpended  to indicate that there was more output than was displayed.  If an evaluated
                     argument contains a space, the entire argument will be enclosed inside of braces (`{}')
                     to allow the reader to visually separate the arguments from each other.

              notruncate
                     Disables the truncation of commands and evaluated arguments.

              procs  Enables  the  tracing  of  procedure  calls only.  Commands that aren't procedure calls
                     (i.e. calls to commands that are written in C, C++ or some object-compatible  language)
                     are  not  traced  if the procs option is specified.  This option is particularly useful
                     for greatly reducing the output of cmdtrace while debugging.

              fileid This is a file id as returned by the open command.  If specified, then the trace output
                     will  be  written  to  the file rather than stdout.  A stdio buffer flush is done after
                     every line is written so that the trace may be monitored externally or  provide  useful
                     information for debugging problems that cause core dumps.

              command cmd

                     Call the specified command cmd on when each command is executed instead of tracing to a
                     file.  See the description of the functionally below.  This option may not be specified
                     with a fileid.

              The most common use of this command is to enable tracing to a file during the development.  If
              a failure occurs, a trace is then available when needed.  Command tracing will slow  down  the
              execution  of code, so it should be removed when code is debugged.  The following command will
              enable tracing to a file for the remainder of the program:

                   cmdtrace on [open cmd.log w]

              The command option causes a user specified trace command to be called for  each  command  exe-cuted. executed.
              cuted.  The command will have the following arguments appended to it before evaluation:

              command
                     A string containing the text of the command, before any argument substitution.

              argv   A  list of the final argument information that will be passed to the command after com-mand, command,
                     mand, variable, and backslash substitution.

              evalLevel
                     The Tcl_Eval call level.

              procLevel
                     The procedure call level.

              The command should be constructed in such a manner that it will work if  additional  arguments
              are  added  in the future.  It is suggested that the command be a proc with the final argument
              being args.

              Tracing will be turned off while the command is being executed.  The values of  the  errorInfo
              and errorCode variables will be saved and restored on return from the command.  It is the com-mand's command's
              mand's responsibility to preserve all other state.

              If an error occurs during the execution of command, an error message is dumped to  stderr  and
              the  tracing  is  disabled.  The underlying mechanism that this functionality is built on does
              not support returning an error to the interpreter.

       cmdtrace off
              Turn off all tracing.

       cmdtrace depth
              Returns the current maximum trace level, or zero if trace is disabled.

       edprocs ?proc...?
              This procedure writes the named procedures, or all currently defined procedures, to  a  tempo-rary temporary
              rary  file, then calls an editor on it (as specified by the EDITOR environment variable, or vi
              if none is specified), then sources the file back in if it was changed.

       profile ?-commands? ?-eval? on

       profile off arrayVar
              This command is used to collect a performance profile of a Tcl script.  It  collects  data  at
              the  Tcl  procedure  level. The number of calls to a procedure, and the amount of real and CPU
              time is collected. Time is also collected for the global context.  The procedure data is  col-lected collected
              lected  by  bucketing  it  based on the procedure call stack, this allows determination of how
              much time is spent in a particular procedure in each of it's calling contexts.

              The on option enables profile data collection. If the -commands option is specified,  data  on
              all  commands within a procedure is collected as well a procedures.  Multiple occurrences of a
              command within a procedure are not distinguished, but this data may still be useful for analy-sis. analysis.
              sis.

              The  off  option  turns off profiling and moves the data collected to the array arrayVar.  The
              array is address by a list containing the procedure call stack.  Element zero is  the  top  of
              the stack, the procedure that the data is for.  The data in each entry is a list consisting of
              the procedure call count and the real time and CPU time in milliseconds spent in the procedure
              (but not any procedures it calls). The list is in the form {count real cpu}.

              Normally,  the  variable scope stack is used in reporting where time is spent.  Thus upleveled
              code is reported in the context that it was executed in, not the context that the uplevel  was
              called  in.   If  the -eval option is specified, the procedure evaluation (call) stack is used
              instead of the procedure scope stack.  Upleveled code is reported in the context of the proce-dure procedure
              dure that did the uplevel.

              A Tcl procedure profrep is supplied for reducing the data and producing a report.

              On  Windows,  profile command only reports elapsed real time, CPU time is not available and is
              reported as zero.

       profrep profDataVar sortKey ?outFile? ?userTitle?
              This procedure generates a report from data collect from the profile command.  ProfDataVar  is
              the  name  of the array containing the data returned by the profile command. SortKey indicates
              which data value to sort by.  It should be one of "calls", "cpu" or "real".   OutFile  is  the
              name of file to write the report to.  If omitted, stdout is assumed.  UserTitle is an optional
              title line to add to output.

              Listed with indentation below each procedure or command is  the  procedure  call  stack.   The
              first  indented  line being the procedure that invoked the reported procedure or command.  The
              next line is the procedure that invoked the procedure above it, and so  on.   If  no  indented
              procedures are shown, the procedure or command was called from the global context.  Time actu-ally actually
              ally spent in the global context is listed on a line  labeled  <global>.   Upleveled  code  is
              reported  in  the context that it was executed in, not the context that the uplevel was called
              in.

       saveprocs fileName ?proc...?
              This procedure saves the definition of the named procedure, or all  currently  defined  proce-dures procedures
              dures if none is specified, to the named file.

UNIX ACCESS COMMANDS
       These  commands  provide  access  to many basic Unix facilities, including process handling, date and
       time processing, signal handling and the executing commands via the shell.

       alarm seconds
              Instructs the system to send a SIGALRM signal in the specified number of seconds.  This  is  a
              floating  point  number,  so  fractions of a section may be specified.  If seconds is 0.0, any
              previous alarm request is canceled.  Only one alarm at a  time  may  be  active;  the  command
              returns  the  number  of seconds left in the previous alarm.  On systems without the setitimer
              system call, seconds is rounded up to an integer number of seconds.

              The alarm command is not available on Windows.

       execl ?-argv0 argv0? prog ?arglist?
              Do an execl, replacing the current  program  (either  Extended  Tcl  or  an  application  with
              Extended Tcl embedded into it) with prog and passing the arguments in the list arglist.

              The -argv0 options specifies that argv_ is to be passed to the program as argv [0] rather than
              prog.

              Note: If you are using execl in a Tk application and it fails, you may not  do  anything  that
              accesses  the X server or you will receive a BadWindow error from the X server.  This includes
              executing the Tk version of the exit command.  We suggest using the following command to abort
              Tk applications after an execl failure:

                  kill [id process]

              On  Windows,  where  the fork command is not available, execl starts a new process and returns
              the process id.

       chroot dirname
              Change root directory to dirname, by invoking the POSIX chroot(2) system call.   This  command
              only succeeds if running as root.

       fork   Fork  the  current Tcl process.  Fork returns zero to the child process and the process number
              of the child to the parent process.  If the fork fails, a Tcl error is generated.

              If an execl is not going to be performed before the child process does output, or if  a  close
              and  dup  sequence is going to be performed on stdout or stderr, then a flush should be issued
              against stdout, stderr and any other open output file before doing the fork. Otherwise charac-ters characters
              ters  from  the  parent  process  pending in the buffers will be output by both the parent and
              child processes.

              Note: If you are forking in a Tk based application you must  execl  before  doing  any  window
              operations in the child or you will receive a BadWindow error from the X server.

              The fork command is not available on Windows.

       id options

              This  command provides a means of getting, setting and converting user, group and process ids.
              The id command has the following options:

              id user ?name?

              id userid ?uid?
                     Set the real and effective user ID to name or uid, if the name (or uid)  is  valid  and
                     permissions allow it.  If the name (or uid) is not specified, the current name (or uid)
                     is returned.

              id convert userid uid

              id convert user name
                     Convert a user ID number to a user name, or vice versa.

              id group ?name?

              id groupid ?gid?
                     Set the real and effective group ID to name or gid, if the name (or gid) is  valid  and
                     permissions  allow  it.  If the group name (or gid) is not specified, the current group
                     name (or gid) is returned.

              id groups

              id groupids
                     Return the current group access list of the process.  The option groups  returns  group
                     names and groupids returns id numbers.

              id convert groupid gid

              id convert group name
                     Convert a group ID number to a group name, or vice versa.

              id effective user

              id effective userid
                     Return the effective user name, or effective user ID number, respectively.

              id effective group

              id effective groupid
                     Return the effective group name, or effective group ID number, respectively.

              id effective groupids
                     Return all of the groupids the user is a member of.

              id host
                     Return the hostname of the system the program is running on.

              id process
                     Return the process ID of the current process.

              id process parent
                     Return the process ID of the parent of the current process.

              id process group
                     Return the process group ID of the current process.

              id process group set
                     Set the process group ID of the current process to its process ID.

              id host
                     Returns the standard host name of the machine the process is executing on.

                     On Windows, only the host and process options are implemented.

       kill ?-pgroup ?signal? idlist

              Send  a  signal  to the each process in the list idlist, if permitted.  Signal, if present, is
              the signal number or the symbolic name of the signal, see the signal system call manual  page.
              The  leading  ``SIG''  is  optional  when  the  signal is specified by its symbolic name.  The
              default for signo is 15, SIGTERM.

              If -pgroup is specified, the numbers in idlist are take as process group ids and the signal is
              sent  to all of the process in that process group.  A process group id of 0 specifies the cur-rent current
              rent process group.

              On Windows, the kill command is capable of terminating a process, but not of sending an  arbi-trary arbitrary
              trary signal.

       link ?-sym? srcpath destpath

              Create  a  directory  entry,  destpath,  linking it to the existing file, srcpath.  If -sym is
              specified, a symbolic link, rather than a hard link, is created.  (The  -sym  option  is  only
              available on systems that support symbolic links.)

              The link command is not available on Windows.  Use the Tcl 8.4+ file link command instead.

       nice ?priorityincr?

              Change  or  return  the process priority.  If priorityincr is omitted, the current priority is
              returned.  If priorityincr is positive, it is added to the current priority  level,  up  to  a
              system defined maximum (normally 19),

              Negative  priorityincr  values  cumulatively  increase the program's priority down to a system
              defined minimum (normally -19); increasing priority with negative niceness  values  will  only
              work for the superuser.

              The new priority is returned.

              The nice command is not available on Windows.

       readdir ?-hidden? dirPath

              Returns  a  list  containing the contents of the directory dirPath.  The directory entries "."
              and ".." are not returned.

              On Windows, -hidden maybe specified to include hidden files  in  the  result.   This  flag  is
              ignored on Unix systems.

       signal ?-restart? action siglist ?command?

              Warning:  If signals are being used as an event source (a trap action), rather than generating
              an error to terminate a task; one must use the -restart option.  This causes a blocked  system
              call,  such  as  read or waitpid to be restarted rather than generate an error.  Failure to do
              this may results in unexpected errors when a signal arrives  while  in  one  of  these  system
              calls.  When available, the -restart option can prevent this problem.

              If  -restart is specified, restart blocking system calls rather than generating an error.  The
              signal will be handled once the Tcl command  that  issued  the  system  call  completes.   The
              -restart  options is not available on all operating systems and its use will generate an error
              when it is not supported.  Use infox have_signal_restart to check for availability.

              Specify the action to take when a Unix signal is received by Extended Tcl, or a  program  that
              embeds it.  Siglist is a list of either the symbolic or numeric Unix signal (the SIG prefix is
              optional).  Action is one of the following actions to be performed on receipt of  the  signal.
              To specify all modifiable signals, use `*' (this will not include SIGKILL and SIGSTOP, as they
              can not be modified).

              default
                     Perform system default action when signal is received (see signal system call  documen-tation). documentation).
                     tation).

              ignore Ignore the signal.

              error  Generate a catchable Tcl error.  It will be as if the command that was running returned
                     an error.  The error code will be in the form:
                          POSIX SIG signame
                     For the death of child signal, signame will always be SIGCHLD, rather than  SIGCLD,  to
                     allow writing portable code.

              trap   When  the  signal  occurs,  execute  command  and continue execution if an error is not
                     returned by command.  The command will be executed in the global context.  The  command
                     will  be  edited  before execution, replacing occurrences of "%S" with the signal name.
                     Occurrences of "%%" result in a single "%".  This editing occurs just before  the  trap
                     command  is  evaluated.   If  an  error is returned, then follow the standard Tcl error
                     mechanism.  Often command will just do an exit.

              get    Retrieve the current settings of the specified signals.  A keyed list will be  returned
                     were  the keys are one of the specified signals and the values are a list consisting of
                     the action associated with the signal, a 0 if the signal may be delivered  (not  block)
                     and  a 1 if it is blocked and a flag indicating if restarting of system calls is speci-fied. specified.
                     fied.  The actions maybe one of `default',`ignore', `error' or `trap'.  If  the  action
                     is  trap,  the  third  element  is  the command associated with the action.  The action
                     `unknown' is returned if a non-Tcl signal handler has been associated with the  signal.

              set    Set  signals  from  a  keyed  list in the format returned by the get.  For this action,
                     siglist is the keyed list of signal state.  Signals with an action of `unknown' are not
                     modified.

              block  Block the specified signals from being received. (Posix systems only).

              unblock
                     Allow  the specified signal to be received. Pending signals will not occur. (Posix sys-tems systems
                     tems only).

              The signal action will remain enabled after the specified signal has occurred.  The  exception
              to  this  is  SIGCHLD  on systems without Posix signals.  For these systems, SIGCHLD is not be
              automatically reenabled.  After a SIGCHLD signal is received, a call to wait must be performed
              to  retrieve  the  exit  status of the child process before issuing another signal SIGCHLD ...
              command.  For code that is to be portable between both types of systems, use this approach.

              Signals are not processed until after the completion of the Tcl command that is executing when
              the  signal  is received.  If an interactive Tcl shell is running, then the SIGINT will be set
              to error, non-interactive Tcl sessions leave SIGINT unchanged from when  the  process  started
              (normally default for foreground processes and ignore for processes in the background).

       sleep seconds
              Sleep  the  Extended Tcl process for seconds seconds.  Seconds, if specified as a decimal num-ber, number,
              ber, is truncated to an integer value.

       system cmdstr1 ?cmdstr2...?
              Concatenates  cmdstr1,  cmdstr2 etc with space separators (see the concat command) into a sin-gle single
              gle  command and then evaluates the command using the standard system shell.  On Unix systems,
              this is /bin/sh and on Windows its command.com.  The exit code of the command is returned.

              This command differs from the exec command in that system doesn't  return  the  executed  com-mand's command's
              mand's standard output as the result string, and system goes through the Unix shell to provide
              wild card expansion, redirection, etc, as is normal from an sh command line.

       sync ?fileId?

              If fileId is not specified, or if it is and this system does  not  support  the  fsync  system
              call,  issues a sync system call to flush all pending disk output.  If fileId is specified and
              the system does support the fsync system call, issues an fsync on the  file  corresponding  to
              the specified Tcl fileId to force all pending output to that file out to the disk.

              If  fileId is specified, the file must be writable.  A flush will be issued against the fileId
              before the sync.

              The infox have_fsync command can be used to determine if "sync fileId" will do  a  sync  or  a
              fsync.

       times
              Return a list containing the process and child execution times in the form:
                   utime stime cutime cstime
              Also see the times(2) system call manual page.  The values are in milliseconds.

       umask ?octalmask?
              Sets  file-creation  mode  mask to the octal value of octalmask.  If octalmask is omitted, the
              current mask is returned.

       wait ?-nohang? ?-untraced? ?-pgroup? ?pid?
              Waits for a process created with the execl command to terminate, either due  to  an  untrapped
              signal  or  call  to  exit system call.  If the process id pid is specified, they wait on that
              process, otherwise wait on any child process to terminate.

              If -nohang is specified, then don't block waiting on a process to terminate.  If no process is
              immediately  available,  return  an  empty list.  If -untraced is specified then the status of
              child processes that are stopped, and whose status  has  not  yet  been  reported  since  they
              stopped,  are  also  returned.  If -pgroup is specified and pid is not specified, then wait on
              any child process whose process group ID is they same as the calling process. If pid is speci-fied specified
              fied  with  -pgroup,  then  it  is  take as a process group ID, waiting on any process in that
              process group to terminate.

              Wait returns a list containing three elements: The first element is  the  process  id  of  the
              process  that  terminated.   If the process exited normally, the second element is `EXIT', and
              the third contains the numeric exit code.  If the process terminated due to a signal, the sec-ond second
              ond  element  is  `SIG',  and the third contains the signal name.  If the process is currently
              stopped (on systems that support SIGSTP), the second element is `STOP', followed by the signal
              name.

              Note  that it is possible to wait on processes to terminate that were create in the background
              with the exec command.  However, if any other exec command is executed after the process  ter-minates, terminates,
              minates,  then the process status will be reaped by the exec command and will not be available
              to the wait command.

              On systems without the waitpid system call, the -nohang, -untraced and -pgroup options are not
              available.   The  infox  have_waitpid  command maybe use to determine if this functionality is
              available.

FILE COMMANDS
       These commands provide extended file access and manipulation.  This includes  searching  ASCII-sorted
       data  files,  copying files, duplicating file descriptors, control of file access options, retrieving
       open file status, and creating pipes with the pipe system call.  Also linking  files,  setting  file,
       process,  and user attributes and truncating files.  An interface to the select system call is avail-able available
       able on Unix systems that support it.

       It should be noted that Tcl file I/O is implemented on top of the stdio  library.   By  default,  the
       file  is  buffered.  When communicating to a process through a pipe, a flush command should be issued
       to force the data out.  Alternatively, the fcntl command may be used to set the buffering mode  of  a
       file to line-buffered or unbuffered.

       bsearch fileId key ?retvar? ?compare_proc?
              Search an opened file fileId containing lines of text sorted into ascending order for a match.
              Key contains the string to match.  If retvar is specified, then the  line  from  the  file  is
              returned in retvar, and the command returns 1 if key was found, and 0 if it wasn't.  If retvar
              is not specified or is a null name, then the command returns the line that was  found,  or  an
              empty string if key wasn't found.

              By  default,  the  key  is matched against the first white-space separated field in each line.
              The field is treated as an ASCII string.  If compare_proc is specified, then  it  defines  the
              name  of  a  Tcl  procedure to evaluate against each line read from the sorted file during the
              execution of the bsearch command.  Compare_proc takes  two  arguments,  the  key  and  a  line
              extracted from the file.  The compare routine should return a number less than zero if the key
              is less than the line, zero if the key matches the line, or greater than zero if  the  key  is
              greater  than the line.  The file must be sorted in ascending order according to the same cri-teria criteria
              teria compare_proc uses to compare the key with the line, or erroneous results will occur.

              This command does not work on files containing binary data (bytes of zero).

       chmod [-fileid] mode filelist
              Set permissions of each of the files in the list filelist to mode, where mode is  an  absolute
              numeric  mode  or  symbolic permissions as in the UNIX chmod(1) command.  To specify a mode as
              octal, it should be prefixed with a "0" (e.g. 0622).

              If the option -fileid is specified, filelist is a list of open file identifiers rather than  a
              list  of  file  names.   This  option  is  not  available  on all Unix systems.  Use the infox
              have_fchmod command to determine if this functionality is available.

              The chmod command is not available on Windows.

       chown [-fileid] owner | {owner group} filelist
              Set owner of each file in the list filelist to owner, which can be a user name or numeric user
              id.   If the first parameter is a list, then the owner is set to the first element of the list
              and the group is set to the second element.  Group can be a group name or  numeric  group  id.
              If group is {}, then the file group will be set to the login group of the specified user.

              If  the option -fileid is specified, filelist is a list of open file identifiers rather than a
              list of file names.  This option is  not  available  on  all  Unix  systems.   Use  the  infox
              have_fchown command to determine if this functionality is available.

              The chown command is not available on Windows.

       chgrp [-fileid] group filelist
              Set  the group id of each file in the list filelist to group, which can be either a group name
              or a numeric group id.

              If the option -fileid is specified, filelist is a list of open file identifiers rather than  a
              list  of  file  names.   This  option  is  not  available  on all Unix systems.  Use the infox
              have_fchown command to determine if this functionality is available.

              The chgrp command is not available on Windows.

       dup fileId ?targetFileId?
              Duplicate an open file.  A new file id is opened that addresses the same file as fileId.

              If targetFileId is specified, the the file is dup to this specified file id.  Normally this is
              stdin,  stdout, or stderr.  The dup command will handle flushing output and closing this file.
              The new file will be buffered, if its needs to be unbuffered, use the fcntl command to set  it
              unbuffered.

              If fileId is a number rather than a Tcl file id, then the dup command will bind that file to a
              Tcl file id.  This is useful for accessing files that are passed from the parent process.  The
              argument ?targetFileId? is not valid with this operation.

              On  Windows,  only stdin, stdout, or stderr or a non-socket file handle number maybe specified
              for targetFileId.  The dup command does not work on sockets on Windows.

       fcntl fileId attribute ?value?
              This command either sets or clears a file option or returns its current value.   If  value  is
              not  specified, then the current value of attribute is returned.  All values are boolean. Some
              attributes maybe only be gotten, not modified.  The following attributes may be specified:

       RDONLY The file is opened for reading only. (Get only)

       WRONLY The file is opened for writing only.  (Get only)

       RDWR   The file is opened for reading and writing.  (Get only)

       READ   If the file is readable. (Get only).

       WRITE  If the file is writable. (Get only).

       APPEND The file is opened for append-only writes.  All writes will be forced to the end of the  file.
              (Get or set).

       NONBLOCK
              The  file is to be accessed with non-blocking I/O.  See the read system call for a description
              of how it affects the behavior of file reads.

       CLOEXEC
              Close the file on an process exec.  If the execl command or some other  mechanism  causes  the
              process to do an exec, the file will be closed if this option is set.

       NOBUF  The file is not buffered. If set, then there no buffering for the file.

       LINEBUF
              Output  the  file will be line buffered. The buffer will be flushed when a newline is written,
              when the buffer is full, or when input is requested.

       KEEPALIVE
              Keep a socket connection alive.  If SIGPIPE is enabled, then it is sent if connection is  bro-ken broken
              ken  and  data  is  written to the socket.  If SIGPIPE is ignored, an error is returned on the
              write.  This attribute is valid only on sockets.  By default, SIGPIPE is ignored in Tcl.

              The NONBLOCK, NOBUF and LINEBUF are provided for compatibility with older  scripts.   Thefcon-figure Thefconfigure
              figure command is preferred method of getting and setting these attributes.

              The APPEND and CLOEXEC options are not available on Windows.

       flock options fileId ?start? ?length? ?origin?

              This command places a lock on all or part of the file specified by fileId.  The lock is either
              advisory or mandatory, depending on the mode bits of the file.  The lock is  placed  beginning
              at  relative byte offset start for length bytes.  If start or length is omitted or empty, zero
              is assumed.  If length is zero, then the lock always extents to end of file, even if the  file
              grows.   If origin is "start", then the offset is relative to the beginning of the file. If it
              is "current", it is relative to the current access position in the file.  If it is "end", then
              it  is relative to the end-of-file (a negative is before the EOF, positive is after).  If ori-gin origin
              gin is omitted, start is assumed.

              The following options are recognized:

              -read  Place a read lock on the file.  Multiple processes may be accessing the file with read-locks. readlocks.
                     locks.

              -write Place a write lock on the file.  Only one process may be accessing a file if there is a
                     write lock.

              -nowait
                     If specified, then the process will not block if the lock can not  be  obtained.   With
                     this option, the command returns 1 if the lock is obtained and 0 if it is not.

              See  your  system's  fcntl  system call documentation for full details of the behavior of file
              locking.  If locking is being done on ranges of a file, it is  best  to  use  unbuffered  file
              access (see the fcntl command).

              The flock command is not available on Windows 95.  It is available on Windows NT.

       for_file var filename code
              This  procedure  implements a loop over the contents of a file.  For each line in filename, it
              sets var to the line and executes code.

              The break and continue commands work as with foreach.

              For example, the command

                   for_file line /etc/passwd {echo $line}

              would echo all the lines in the password file.

       funlock fileId ?start? ?length? ?origin?
              Remove a locked from a file that was previously placed with the flock command.  The  arguments
              are the same as for the flock command, see that command for more details.

              The funlock command is not available on Windows 95.  It is available on Windows NT.

       fstat fileId ?item? | ?stat arrayvar?

              Obtain status information about an open file.

              The following keys are used to identify data items:

              atime  The time of last access.

              ctime  The time of last file status change

              dev    The  device  containing  a  directory for the file.  This value uniquely identifies the
                     file system that contains the file.

              gid    The group ID of the file's group.

              ino    The inode number.  This field uniquely identifies the file in a given file system.

              mode   The mode of the file (see the mknod system call).

              mtime  Time when the data in the file was last modified.

              nlink  The number of links to the file.

              size   The file size in bytes.

              tty    If the file is associated with a terminal, then 1 otherwise 0.

              type   The type of the file in symbolic form, which is one  of  the  following  values:  file,
                     directory, characterSpecial, blockSpecial, fifo, link, or socket.

              uid    The user ID of the file's owner.

              If one of these keys is specified as item, then that data item is returned.

              If  stat  arrayvar is specified, then the information is returned in the array arrayvar.  Each
              of the above keys indexes an element of the array containing the data.

              If only fileId is specified, the command returns the data as a keyed list.

              The following values may be returned only if explicitly asked for, it  will  not  be  returned
              with the array or keyed list forms:

              remotehost
                     If fileId is a TCP/IP socket connection, then a list is returned with the first element
                     being the remote host IP address.  If the remote host name can be found, it is returned
                     as  the  second  element of the list.  The remote host IP port number is the third ele-ment. element.
                     ment.

              localhost
                     If fileId is a TCP/IP socket connection, then a list is returned with the first element
                     being  the  local host IP address.  If the local host name can be found, it is returned
                     as the second element of the list.  The local host IP port number is the third element.

       ftruncate [-fileid] file newsize
              Truncate a file to have a length of at most newsize bytes.

              If  the  option  -fileid is specified, file is an open file identifier, otherwise it is a file
              path.

              This command is not available or not fully functional if the underlying operating system  sup-port support
              port  is  not  available.   The  command infox have_truncate will indicate if this command may
              truncate by file path.  The command infox have_ftruncate will indicate  if  this  command  may
              truncate by file id.

              The -fileid option is not available on Windows.

       lgets fileId ?varName?
              Reads  the  next  Tcl  list from the file given by fileId and discards the terminating newline
              character.  This command differs from the gets command, in that it reads Tcl lists rather than
              lines.   If the list contains newlines or binary data, then that newline or bytes of zero will
              be returned as part of the result.  Only a newline not quoted as part of  the  list  indicates
              the  end of the list.  There is no corresponding command for outputting lists, as puts will do
              this correctly.

              If varName is specified, then the line is placed in the variable by that name and  the  return
              value  is a count of the number of characters read (not including the newline).  If the end of
              the file is reached before reading any characters then -1 is returned and varName is set to an
              empty  string.   If  varName is specified and an error occurs, what ever data was read will be
              returned in the variable, however the resulting string may not be a valid list.

              If varName is not specified then the return value will be the line (minus the newline  charac-ter) character)
              ter)  or  an empty string if the end of the file is reached before reading any characters.  An
              empty string will also be returned if a line contains no characters except the newline, so eof
              may have to be used to determine what really happened.

              The  lgets command maybe used to read and write lists containing binary data, however transla-tion translation
              tion must be set to lf or the data maybe corrupted.

              If lgets is currently supported on non-blocking files.

       pipe ?fileId_var_r fileId_var_w?
              Create a pipe.  If fileId_var_r and fileId_var_r are specified, then pipe will set the a vari-able variable
              able  named  fileId_var_r  to  contain  the fileId of the side of the pipe that was opened for
              reading, and fileId_var_w will contain the fileId of the side of the pipe that was opened  for
              writing.

              If  the  fileId variables are not specified, then a list containing the read and write fileIdw
              is returned as the result of the command.

       read_file ?-nonewline? fileName

       read_file fileName numBytes
              This procedure reads the file fileName and returns the contents as a string.  If -nonewline is
              specified,  then  the  last character of the file is discarded if it is a newline.  The second
              form specifies exactly how many bytes will be read and returned, unless there are  fewer  than
              numBytes bytes left in the file; in this case, all the remaining bytes are returned.

       select readfileIds ?writefileIds? ?exceptfileIds? ?timeout?
              This  command allows an Extended Tcl program to wait on zero or more files being ready for for
              reading, writing, have an exceptional condition pending, or for a timeout  period  to  expire.
              readFileIds,  writeFileIds, exceptFileIds are each lists of fileIds, as returned from open, to
              query.  An empty list ({}) may be specified if a category is not used.

              The files specified by the readFileIds list are checked to see if data is available for  read-ing. reading.
              ing.  The  writeFileIds are checked if the specified files are clear for writing.  The except-FileIds exceptFileIds
              FileIds are checked to see if an exceptional condition has  occurred  (typically,  an  error).
              The write and exception checking is most useful on devices, however, the read checking is very
              useful when communicating with multiple processes through pipes.  Select considers data  pend-ing pending
              ing  in  the  stdio input buffer for read files as being ready for reading, the files do.  not
              have to be unbuffered.

              Timeout is a floating point timeout value, in seconds.  If an empty list is supplied  (or  the
              parameter  is omitted), then no timeout is set.  If the value is zero, then the select command
              functions as a poll of the files, returning immediately even if none are ready.

              If the timeout period expires with none of the files becoming ready, then the command  returns
              an empty list.  Otherwise the command returns a list of three elements, each of those elements
              is a list of the fileIds that are ready in the read, write and exception classes.  If none are
              ready in a class, then that element will be the null list.  For example:

                      select {file3 file4 file5} {file6 file7} {} 10.5

              could return

                      {file3 file4} {file6} {}

              or perhaps

                      file3 {} {}

              On  Windows, only sockets can be used with the select command.  Pipes, as returned by the open
              command, are not supported.

       write_file fileName string ?string...?
              This procedure writes the specified strings to the named file.

NETWORK PROGRAMMING SUPPORT
       TclX provides functionality to complement the Tcl socket command.  The host_info command is  used  to
       get  information  about a host by name or IP address.  In addition, the fstat and fcntl commands pro-vide provide
       vide options of querying and controlling connected sockets.  To obtain the host name  of  the  system
       the local system, use the id host command.

       host_info option host
              Obtain  information  about an Internet host. The argument host can be either a host name or an
              IP address.

              The following subcommands are recognized:

              addresses
                     Return the list of IP addresses for host.

              official_name
                     Return official name for host.

              aliases
                     Return the list of aliases for host.  (Note that these are IP number aliases,  not  DNS
                     CNAME aliases. See ifconfig(2).)
FILE SCANNING COMMANDS
       These  commands  provide a facility to scan files, matching lines of the file against regular expres-sions expressions
       sions and executing Tcl code on a match.  With this facility you can use Tcl to do the sort  of  file
       processing  that  is traditionally done with awk.  And since Tcl's approach is more declarative, some
       of the scripts that can be rather difficult to write in awk are simple to code in Tcl.

       File scanning in Tcl centers around the concept of a scan context.  A scan context  contains  one  or
       more  match  statements, which associate regular expressions to scan for with Tcl code to be executed
       when the expressions are matched.

       scancontext ?option?
              This command manages file scan contexts.  A scan context is a collection  of  regular  expres-sions expressions
              sions and commands to execute when that regular expression matches a line of the file.  A con-text context
              text may also have a single default match, to be applied against lines that do not  match  any
              of  the  regular expressions.  Multiple scan contexts may be defined and they may be reused on
              multiple files.  A scan context is identified by a context handle.   The  scancontext  command
              takes the following forms:

       scancontext create
              Create  a  new scan context.  The scanmatch command is used to define patterns in the context.
              A contexthandle is returned, which the Tcl programmer uses to refer to the newly created  scan
              context in calls to the Tcl file scanning commands.

       scancontext delete contexthandle
              Delete  the scan context identified by contexthandle, and free all of the match statements and
              compiled regular expressions associated with the specified context.

       scancontext copyfile contexthandle ?filehandle?
              Set or return the file handle that unmatched lines are copied to.  (See scanfile).   If  file-handle filehandle
              handle  is  omitted, the copy file handle is returned.  If no copy file is associated with the
              context, {} is returned.  If a file handle is specified, it becomes the  copy  file  for  this
              context.  If filehandle is {}, then it removes any copy file specification for the context.

       scanfile ?-copyfile copyFileId? contexthandle fileId
              Scan  the  file  specified by fileId, starting from the current file position.  Check all pat-terns patterns
              terns in the scan context specified by contexthandle against it, executing the match  commands
              corresponding to patterns matched.

              If  the  optional -copyfile argument is specified, the next argument is a file ID to which all
              lines not matched by any pattern (excluding the default pattern) are to be  written.   If  the
              copy  file is specified with this flag, instead of using the scancontext copyfile command, the
              file is disassociated from the scan context at the end of the scan.

              This command does not work on files containing binary data (bytes of zero).

       scanmatch ?-nocase? contexthandle ?regexp? commands

              Specify Tcl commands, to be evaluated when regexp is matched by a scanfile command.  The match
              is  added  to the scan context specified by contexthandle.  Any number of match statements may
              be specified for a give context.  Regexp is a regular expression (see the regexp command).  If
              -nocase  is  specified  as the first argument, the pattern is matched regardless of alphabetic
              case.

              If regexp is not specified, then a default match is  specified  for  the  scan  context.   The
              default  match  will  be  executed  when  a line of the file does not match any of the regular
              expressions in the current scancontext.

              The array matchInfo is available to the Tcl code that is executed when an  expression  matches
              (or  defaults).   It contains information about the file being scanned and where within it the
              expression was matched.

              matchInfo is local to the top level of the match command unless declared global at that  level
              by the Tcl global command.  If it is to be used as a global, it must be declared global before
              scanfile is called (since scanfile sets the matchInfo before the match  code  is  executed,  a
              subsequent  global  will override the local variable).  The following array entries are avail-able: available:
              able:

              matchInfo(line)
                     Contains the text of the line of the file that was matched.

              matchInfo(offset)
                     The byte offset into the file of the first character of the line that was matched.

              matchInfo(linenum)
                     The line number of the line that was matched.  This  is  relative  to  the  first  line
                     scanned,  which is usually, but not necessarily, the first line of the file.  The first
                     line is line number one.

              matchInfo(context)
                     The context handle of the context that this scan is associated with.

              matchInfo(handle)
                     The file id (handle) of the file currently being scanned.

              matchInfo(copyHandle)
                     The file id (handle) of the file specified by the -copyfile option.  The  element  does
                     not exist if -copyfile was not specified.

              matchInfo(submatch0)
                     Will contain the characters matching the first parenthesized subexpression.  The second
                     will be contained in submatch1, etc.

              matchInfo(subindex0)
                     Will contain the a list of the starting and ending indices of the string  matching  the
                     first parenthesized subexpression.  The second will be contained in subindex1, etc.

              All  scanmatch patterns that match a line will be processed in the order in which their speci-fications specifications
              fications were added to the scan context.  The  remainder  of  the  scanmatch  pattern-command
              pairs may be skipped for a file line if a continue is executed by the Tcl code of a preceding,
              matched pattern.

              If a return is executed in the body of the match command, the scanfile  command  currently  in
              progress returns, with the value passed to return as its return value.

MATH COMMANDS
       Several  extended  math  commands commands make many additional math functions available in TclX.  In
       addition, a set of procedures provide command access to the math functions supported by the expr com-mand. command.
       mand.


       The  following  procedures  provide command interfaces to the expr math functions. They take the same
       arguments as the expr functions and may take expressions as arguments.

              abs         acos        asin       atan2
              atan        ceil        cos        cosh
              double      exp         floor      fmod
              hypot       int         log10      log
              pow         round       sin        sinh
              sqrt        tan         tanh

       max num1 ?..numN?

       expr max(num1, num2)
              Returns the argument that has the highest numeric value. Each argument may be any  integer  or
              floating point value.

              This functionality is also available as a math function max in the Tcl expr command.

       min num1 ?..numN?

       expr min(num1, num2)
              Returns  the  argument that has the lowest numeric value.  Each argument may be any integer or
              floating point value.

              This functionality is also available as a math function min in the Tcl expr command.

       random limit | seed ?seedval?
              Generate a pseudorandom integer number greater than or equal to zero and less than limit.   If
              seed  is  specified,  then  the command resets the random number generator to a starting point
              derived from the seedval. This allows one to reproduce pseudorandom number sequences for test-ing testing
              ing  purposes.  If seedval is omitted, then the seed is set to a value based on current system
              state and the current time, providing a reasonably interesting and ever-changing seed.

LIST MANIPULATION COMMANDS
       Extended Tcl provides additional list manipulation commands and procedures.

       intersect lista listb
              Procedure to return the logical intersection of two lists.  The returned list will be  sorted.

       intersect3 lista listb
              Procedure  to  intersects  two lists, returning a list containing three lists:  The first list
              returned is everything in lista that wasn't in listb.  The second list contains the  intersec-tion intersection
              tion  of  the  two  lists, and the third list contains all the elements that were in listb but
              weren't in lista.  The returned lists will be sorted.

       lassign list var ?var...?
              Assign successive elements of a list to specified variables.  If there are more variable names
              than  fields, the remaining variables are set to the empty string.  If there are more elements
              than variables, a list of the unassigned elements is returned.

              For example,

                  lassign {dave 100 200 {Dave Foo}} name uid gid longName

              Assigns name to ``dave'', uid to ``100'', gid to ``200'', and longName to ``Dave Foo''.

       lcontain list element
              Determine if the element is a list element of list.  If the element is contained in the  list,
              1 is returned, otherwise, 0 is returned.

       lempty list
              Determine  if the specified list is empty.  If empty, 1 is returned, otherwise, 0 is returned.
              This command is an alternative to comparing a list to an empty string, however it checks for a
              string of all whitespaces, which is an empty list.

       lmatch ?mode? list pattern

              Search  the  elements  of  list,  returning  a list of all elements matching pattern.  If none
              match, an empty list is returned.

              The mode argument indicates how the elements of the list are to be matched against pattern and
              it must have one of the following values:

              -exact The list element must contain exactly the same string as pattern.

              -glob  Pattern  is  a  glob-style pattern which is matched against each list element using the
                     same rules as the string match command.

              -regexp
                     Pattern is treated as a regular expression and matched against each list element  using
                     the same rules as the regexp command.

              If mode is omitted then it defaults to -glob.

              Only the -exact comparison will work on binary data.

       lrmdups list
              Procedure to remove duplicate elements from a list.  The returned list will be sorted.

       lvarcat var string ?string...?
              This  command  treats  each  string argument as a list and concatenates them to the end of the
              contents of var, forming a a single list.  The list is stored back into var and also  returned
              as the result.  if var does not exist, it is created.

       lvarpop var ?indexExpr? ?string?
              The  lvarpop  command  pops (deletes) the element indexed by the expression indexExpr from the
              list contained in the variable var.  If index is omitted, then 0 is assumed.   If  string,  is
              specified,  then the deleted element is replaced by string. The replaced or deleted element is
              returned.  Thus ``lvarpop argv 0'' returns the first element of argv, setting argv to  contain
              the remainder of the string.

              If the expression indexExpr starts with the string end, then end is replaced with the index of
              the last element in the list.  If the expression starts with len, then len  is  replaced  with
              the length of the list.

       lvarpush var string ?indexExpr?
              The  lvarpush command pushes (inserts) string as an element in the list contained in the vari-able variable
              able var.  The element is inserted before position indexExpr in the list. If index is omitted,
              then 0 is assumed.  If var does not exists, it is created.

              If the expression indexExpr starts with the string end, then end is replaced with the index of
              the last element in the list.  If the expression starts with len, then len  is  replaced  with
              the  length of the list.  Note the a value of end means insert the string before the last ele-ment. element.
              ment.

       union lista listb
              Procedure to return the logical union of the two specified lists.  Any duplicate elements  are
              removed.

KEYED LISTS
       Extended  Tcl  defines  a  special  type  of list referred to as keyed lists.  These lists provided a
       structured data type built upon standard Tcl lists.  This provides a functionality similar to structs
       in the C programming language.

       A  keyed list is a list in which each element contains a key and value pair.  These element pairs are
       stored as lists themselves, where the key is the first element of the list, and the value is the sec-ond. second.
       ond.  The key-value pairs are referred to as fields.  This is an example of a keyed list:

                  {{NAME {Frank Zappa}} {JOB {musician and composer}}}

       If the variable person contained the above list, then keylget person NAME would return {Frank Zappa}.
       Executing the command:

                   keylset person ID 106

       would make person contain

                  {{ID 106} {NAME {Frank Zappa}} {JOB {musician and composer}}

       Fields may contain subfields; `.' is the separator character.  Subfields are  actually  fields  where
       the  value  is another keyed list.  Thus the following list has the top level fields ID and NAME, and
       subfields NAME.FIRST and  NAME.LAST:

                  {ID 106} {NAME {{FIRST Frank} {LAST Zappa}}}

       There is no limit to the recursive depth of subfields, allowing one to build complex data structures.

       Keyed  lists  are  constructed and accessed via a number of commands.  All keyed list management com-mands commands
       mands take the name of the variable containing the keyed list as an argument (i.e. passed  by  refer-ence), reference),
       ence), rather than passing the list directly.

       keyldel listvar key
              Delete  the  field specified by key from the keyed list in the variable listvar.  This removes
              both the key and the value from the keyed list.

       keylget listvar ?key? ?retvar | {}?
              Return the value associated with key from the keyed list in the variable listvar.   If  retvar
              is not specified, then the value will be returned as the result of the command.  In this case,
              if key is not found in the list, an error will result.

              If retvar is specified and key is in the list, then the value is returned in the variable ret-var retvar
              var  and  the  command  returns 1 if the key was present within the list.  If key isn't in the
              list, the command will return 0, and retvar will be left unchanged.  If {}  is  specified  for
              retvar,  the  value  is  not  returned,  allowing  the Tcl programmer to determine if a key is
              present in a keyed list without setting a variable as a side-effect.

              If key is omitted, then a list of all the keys in the keyed list is returned.

       keylkeys listvar ?key?
              Return the a list of the keys in the keyed list in the variable listvar.  If  keys  is  speci-fied, specified,
              fied, then it is the name of a key field  who's subfield keys are to be retrieve.

       keylset listvar key value ?key2 value2 ...?
              Set  the  value  associated  with key, in the keyed list contained in the variable listvar, to
              value.  If listvar does not exists, it is created.  If key is not currently in  the  list,  it
              will  be  added.   If it already exists, value replaces the existing value.  Multiple keywords
              and values may be specified, if desired.

STRING AND CHARACTER MANIPULATION COMMANDS
       The commands provide additional functionality to  classify  characters,  convert  characters  between
       character  and numeric values, index into a string, determine the length of a string, extract a range
       of character from a string, replicate a string a number of times, and transliterate a string (similar
       to the Unix tr program).

       ccollate ?-local? string1 string2
              This  command  compares two strings.  If returns -1 if string1 is less than string2, 0 if they
              are equal and 1 if string1 is greater than string2.

              If -local is specified, the strings are compared according to the collation environment of the
              current locale.

              This command does not work with binary or UTF data.

       cconcat ?string1? ?string2? ?...?
              Concatenate the arguments, returning the resulting string.  While string concatenation is nor-mally normally
              mally performed by the parser, it is occasionally useful to have  a  command  that  returns  a
              string.   The  is  generally useful when a command to evaluate is required.  No separators are
              inserted between the strings.

              This command is UTF-aware.

       cequal string string
              This command compares two strings for equality.  It returns 1 if string1 and string2  are  the
              identical  and  0  if they are not.  This command is a short-cut for string compare and avoids
              the problems with string expressions being treated unintentionally as numbers.

              This command is UTF-aware and will also work on binary data.

       cindex string indexExpr
              Returns the character indexed by the expression indexExpr (zero based) from string.

              If the expression indexExpr starts with the string end, then end is replaced with the index of
              the  last  character  in  the string.  If the expression starts with len, then len is replaced
              with the length of the string.

              This command is UTF-aware.

       clength string
              Returns the length of string in characters.  This command is a shortcut for:
                  string length string

              This command is UTF-aware.

       crange string firstExpr lastExpr
              Returns a range of characters from string starting at the character indexed by the  expression
              firstExpr (zero-based) until the character indexed by the expression lastExpr.

              If  the expression firstExpr or lastExpr starts with the string end, then end is replaced with
              the index of the last character in the string.  If the expression starts with len, then len is
              replaced with the length of the string.

              This command is UTF-aware.

       csubstr string firstExpr lengthExpr
              Returns  a range of characters from string starting at the character indexed by the expression
              firstExpr (zero-based) for lengthExpr characters.

              If the expression firstExpr or lengthExpr starts with the string end,  then  end  is  replaced
              with  the  index of the last character in the string.  If the expression starts with len, then
              len is replaced with the length of the string.

              This command is UTF-aware.

       ctoken strvar separators
              Parse a token out of a character string.  The string to parse is  contained  in  the  variable
              named strvar.  The string separators contains all of the valid separator characters for tokens
              in the string.  All leading separators are skipped and the first token is returned.  The vari-able variable
              able strvar will be modified to contain the remainder of the string following the token.

              This command does not work with binary data.

       ctype ?-failindex var? class string
              ctype determines whether all characters in string are of the specified class.  It returns 1 if
              they are all of class, and 0 if they are not, or if the string is empty.   This  command  also
              provides another method (besides format and scan) of converting between an ASCII character and
              its numeric value.  The following ctype commands are available:

              ctype ?-failindex var? alnum string
                     Tests that all characters are alphabetic or numeric characters as defined by the  char-acter character
                     acter set.

              ctype ?-failindex var? alpha string
                     Tests that all characters are alphabetic characters as defined by the character set.

              ctype ?-failindex var? ascii string
                     Tests  that  all  characters  are  an  ASCII character (a non-negative number less than
                     0200).

              ctype char number
                     Converts the numeric value, string, to an ASCII character.  Number must be in the range
                     0 through the maximum Unicode values.

              ctype ?-failindex var? cntrl string
                     Tests that all characters are ``control characters'' as defined by the character set.

              ctype ?-failindex var? digit string
                     Tests that all characters are valid decimal digits, i.e. 0 through 9.

              ctype ?-failindex var? graph string
                     Tests  that  all  characters  within  are  any character for which ctype print is true,
                     except for space characters.

              ctype ?-failindex var? lower string
                     Tests that all characters are lowercase letters as defined by the character set.

              ctype ord character
                     Convert a character into its decimal numeric value.  The first character of the  string
                     is converted to its numeric Unicode value.

              ctype ?-failindex var? space string
                     Tests that all characters are either a space, horizontal-tab, carriage return, newline,
                     vertical-tab, or form-feed.

              ctype ?-failindex var? print string
                     Tests that all characters are a space or any character for which ctype alnum  or  ctype
                     punct is true or other ``printing character'' as defined by the character set.

              ctype ?-failindex var? punct string
                     Tests  that all characters are made up of any of the characters other than the ones for
                     which alnum, cntrl, or space is true.

              ctype ?-failindex var? upper string
                     Tests that all characters are uppercase letters as defined by the character set.

              ctype ?-failindex var? xdigit string
                     Tests that all characters are valid hexadecimal digits, that is _ through 9, a  through
                     f or A through F.

              If  -failindex  is  specified,  then the index into string of the first character that did not
              match the class is returned in var.

       replicate string countExpr
              Returns string, replicated the number of times indicated by the expression countExpr.

              This command is UTF-aware and will work with binary data.

       translit inrange outrange string
              Translate characters in string, changing characters occurring in inrange to the  corresponding
              character  in  outrange. Inrange and outrange may be list of characters or a range in the form
              `A-M'.  For example:
                      translit a-z A-Z foobar

              This command currently only supports characters in ASCII range; UTF-8 characters
              out of this range will generate an error.

XPG/3 MESSAGE CATALOG COMMANDS
       These commands provide a Tcl interface to message catalogs that are compliant with the X/Open  Porta-bility Portability
       bility Guide, Version 3 (XPG/3).

       Tcl  programmers  can  use  message  catalogs  to  create applications that are language-independent.
       Through the use of message catalogs, prompts, messages, menus and so forth can exist for  any  number
       of  languages,  and they can altered, and new languages added,  without affecting any Tcl or C source
       code, greatly easing the maintenance difficulties incurred by supporting multiple languages.

       A default text message is passed to the command that fetches entries  from  message  catalogs.   This
       allows  the  Tcl  programmer to create message catalogs containing messages in various languages, but
       still have a set of default messages available regardless of the presence of  any  message  catalogs,
       and allow the programs to press on without difficulty when no catalogs are present.

       Thus,  the  normal  approach  to using message catalogs is to ignore errors on catopen, in which case
       catgets will return the default message that was specified in the call.

       The Tcl message catalog commands normally ignore most errors.  If it is desirable to detect errors, a
       special option is provided.  This is normally used only during debugging, to insure that message cat-alogs catalogs
       alogs are being used.  If your Unix implementation does not have XPG/3 message catalog support, stubs
       will  be  compiled  in  that will create a version of catgets that always returns the default string.
       This allows for easy porting of software to environments that don't have support  for  message  cata-logs. catalogs.
       logs.

       Message  catalogs are global to the process, an application with multiple Tcl interpreters within the
       same process may pass and share message catalog handles.

       catopen ?-fail | -nofail? catname
              Open the message catalog catname.  This may be a relative path name, in which case the NLSPATH
              environment variable is searched to find an absolute path to the message catalog.  A handle in
              the form msgcatN is returned.  Normally, errors are ignored, and in the case of a failed  call
              to  catopen,  a  handle is returned to an unopened message catalog.  (This handle may still be
              passed to catgets and catclose, causing catgets  to  simply  return  the  default  string,  as
              described  above.   If  the -fail option is specified, an error is returned if the open fails.
              The option -nofail specifies the default behavior of not returning an error when catopen fails
              to  open  a  specified message catalog.  If the handle from a failed catopen is passed to cat-gets, catgets,
              gets, the default string is returned.

       catgets catHandle setnum msgnum defaultstr
              Retrieve a message form a message catalog. CatHandle should be a Tcl  message  catalog  handle
              that  was  returned  by  catopen.  Setnum is the message set number, and msgnum is the message
              number. If the message catalog was not opened, or the message set or message number cannot  be
              found, then the default string, defaultstr, is returned.

       catclose ?-fail | -nofail? cathandle
              Close  the message catalog specified by cathandle.  Normally, errors are ignored.  If -fail is
              specified, any errors closing the message catalog file are returned.  The option -nofail spec-ifies specifies
              ifies the default behavior of not returning an error.  The use of -fail only makes sense if it
              was also specified in the call to catopen.

       mainloop
              This procedure sets up a top-level event loop.  Events are processed until there are  no  more
              active  event  sources,  at  which time the process exits.  It is used to build event oriented
              programs using the TclX shell in a style similar to that used with wish.  If the global  vari-able variable
              able  tcl_interactive exists and has a true value an interactive command handler is started as
              well.   If the command handler is terminated by an EOF, the process will be exited.

HELP FACILITY
       The help facility allows one to look up help pages which where extracted from the standard Tcl manual
       pages  and  Tcl  scripts  during Tcl installation.  Help files are structured as a multilevel tree of
       subjects and help pages.  Help files are found by searching directories named help in the directories
       listed  in  the  auto_path variable.  All of the files in the list of help directories form a virtual
       root of the help tree.  This method allows multiple applications to provide help trees without having
       the files reside in the same directory.

       The  help  facility can be accessed in two ways, as interactive commands in the Extended Tcl shell or
       as an interactive Tk-based program (if you have built Extended Tcl with Tk).

       To run the Tk-based interactive help program:

           tclhelp ?addpaths?

       Where addpaths are additional paths to search for help directories.  By default, only  the  auto_path
       used by tclhelp is search.  This will result in help on Tcl, Extended Tcl and Tk.

       The following interactive Tcl commands and options are provided with the help package:

       help
              Help,  without arguments, lists of all the help subjects and pages under the current help sub-ject. subject.
              ject.

       help subject
              Displays all of help pages and lower level subjects (if any exist) under the subject  subject.

       help subject/helppage
              Display  the  specified help page.  The help output is passed through a simple pager if output
              exceeds 23 lines, pausing waiting for a return to be  entered.   If  any  other  character  is
              entered, the output is terminated.

       helpcd ?subject?
              Change  the current subject, which is much like the Unix current directory.  If subject is not
              specified, return to the top-level of the help tree.  Help subject path names may also include
              ``..'' elements.

       helppwd
              Displays the current help subject.

       help help | ?
              Displays help on the help facility at any directory level.

       apropos pattern
              This command locates subjects by searching their one-line descriptions for a pattern.  Apropos
              is useful when you can remember part of the name or description of  a  command,  and  want  to
              search  through  the  one-line  summaries for matching lines.  Full regular expressions may be
              specified (see the regexp command).

TCL LOADABLE LIBRARIES AND PACKAGES
       Extended Tcl supports standard Tcl tclIndex libraries and package libraries. A package  library  file
       can contain multiple independent Tcl packages.  A package is a named collection of related Tcl proce-dures procedures
       dures and initialization code.

       The package library file is just a regular Unix text file, editable with your favorite  text  editor,
       containing packages of Tcl source code. The package library file name must have the suffix .tlib.  An
       index file with the same prefix name and the suffix .tndx resides the same  directory  as  the  .tlib
       file.   The .tndx will be automatically created whenever it is out of date or missing (provided there
       is write access to the directory).

       The variable auto_path contains a list of directories that are searched  for  libraries.   The  first
       time  an  unknown  command trap is take, the indexes for the libraries are loaded into memory. If the
       auto_path variable is changed during execution of a program, it will be re-searched. Only  the  first
       package  of  a  given name found during the execution of a program is loaded.  This can be overridden
       with loadlibindex command.

       The start of a package is delimited by:

              #@package: package_name proc1 ?..procN?

       These lines must start in column one.  Everything between the #@package: keyword and the next #@pack-age: #@package:
       age:  keyword or a #@packend keyword, or the end of the file, becomes part of the named package.  The
       specified procedures, proc1..procN, are the entry points of the package.  When a command named  in  a
       package specification is executed and detected as an unknown command, all code in the specified pack-age package
       age will be sourced.  This package should define all of the procedures named  on  the  package  line,
       define  any  support  procedures  required by the package and do any package-specific initialization.
       Packages declarations maybe continued on subsequent lines using standard Tcl backslash line continua-tions. continuations.
       tions.   The  #@packend  keyword  is useful to make sure only the minimum required section of code is
       sourced.  Thus for example a large comment block at the beginning of the next file won't be loaded.

       Care should be taken in defining package_name, as the first package found in the path by with a given
       name is loaded.  This can be useful in developing new version of packages installed on the system.

       For example, in a package source file, the presence of the following line:

              #@package: directory_stack pushd popd dirs

       says  that  the text lines following that line in the package file up to the next package line or the
       end of the file is a package named directory_stack and that an attempt to execute either pushd,  popd
       or dirs when the routine is not already defined will cause the directory_stack portion of the package
       file to be loaded.

PACKAGE LIBRARY MANAGEMENT COMMANDS
       Several commands are available for building  and  managing  package  libraries.   Commands  that  are
       extended  versions  of  the  standard  Tcl library commands are listed here.  All of the standard Tcl
       library management commands and variables are also supported.

       auto_commands ?-loaders?
              Lists the names of all known loadable procedures and  commands  procedures.   If  -loaders  is
              specified, the command that will be executed to load the command will also be returned.

       buildpackageindex libfilelist
              Build  index  files  for  package  libraries.   The  argument libfilelist is a list of package
              libraries.  Each name must end with the suffix .tlib.  A  corresponding  .tndx  file  will  be
              built.  The user must have write access to the directory containing each library.

       convert_lib tclIndex packagelib ?ignore?
              Convert  a  Ousterhout  style  tclIndex  index  file and associate source files into a package
              library packagelib.  If packagelib does not have a .tlib extension, one will  be  added.   Any
              files  specified  in  tclIndex  that  are in the list ignore will be skipped.  Files listed in
              ignore should just be the base file names, not full paths.

       loadlibindex libfile.tlib
              Load the package library index of the library file libfile (which must have the suffix .tlib).
              Package library indexes along the auto_path are loaded automatically on the first demand_load;
              this command is provided to explicitly load libraries that are not in the path.  If the  index
              file  (with  a .tndx suffix) does not exists or is out of date, it will be rebuilt if the user
              has directory permissions to create it. If a package with the same name as a package  in  lib-file.tlib libfile.tlib
              file.tlib has already been loaded, its definition will be overridden by the new package.  How-ever, However,
              ever, if any procedure has actually been used from the previously defined package, the  proce-dures procedures
              dures from libfile.tlib will not be loaded.

       auto_packages ?-location?
              Returns  a  list  of  the  names of all defined packages. If -location is specified, a list of
              pairs of package name and the .tlib path name, offset and length of  the  package  within  the
              library.

       auto_load_file file
              Source a file, as with the source command, except search auto_path for the file.

       searchpath path file
              Search  all  directories  in  the specified path, which is a Tcl list, for the specified file.
              Returns the full path name of the file, or an empty string if the requested file could not  be
              found.





Tcl                                                                                                TclX(TCL)

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