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IO::Pager(3)                         User Contributed Perl Documentation                        IO::Pager(3)



NAME
       IO::Pager - Select a pager, optionally pipe it output if destination is a TTY

SYNOPSIS
         #Select a pager, sets $ENV{PAGER}
         use IO::Pager;

         #Optionally pipe output
         {
           #local $STDOUT =     IO::Pager::open *STDOUT;
           local  $STDOUT = new IO::Pager       *STDOUT;
           print <<"  HEREDOC" ;
           ...
           A bunch of text later
           HEREDOC
         }

DESCRIPTION
       IO::Pager is lightweight and can be used to locate an available pager and set $ENV{PAGER} (see
       "NOTES") or as a factory for creating objects defined elsewhere such as IO::Pager::Buffered and
       IO::Pager::Unbuffered.

       IO::Pager subclasses are designed to programmatically decide whether or not to pipe a filehandle's
       output to a program specified in $ENV{PAGER}.  Subclasses are only required to support filehandle
       output methods and close, namely

       CLOSE
           Supports close() of the filehandle.

       PRINT
           Supports print() to the filehandle.

       PRINTF
           Supports printf() to the filehandle.

       WRITE
           Supports syswrite() to the filehandle.

       For anything else, YMMV.

   new( [FILEHANDLE], [EXPR] )
       Instantiate a new IO::Pager to paginate FILEHANDLE if necessary.  Assign the return value to a scoped
       variable.

       See the appropriate subclass for implementation specific details.

       FILEHANDLE
           Defaults to currently select()-ed FILEHANDLE.

       EXPR
           An expression which evaluates to the subclass of object to create.

           Defaults to IO::Pager::Unbuffered.

   open( [FILEHANDLE], [EXPR] )
       An alias for new.

   close( FILEHANDLE )
       Explicitly close the filehandle, this stops any redirection of output on FILEHANDLE that may have
       been warranted. Normally you'd just wait for the object to pass out of scope.

       This does not default to the current filehandle.

       See the appropriate subclass for implementation specific details.

ENVIRONMENT
       PAGER
           The location of the default pager.

       PATH
           If PAGER does not specify an absolute path for the binary PATH may be used.

           See "NOTES" for more information.

FILES
       IO::Pager may fall back to these binaries in order if $ENV{PAGER} is not executable.

       /usr/local/bin/less
       /usr/bin/less
       /usr/bin/more

       See "NOTES" for more information.

NOTES
       The algorythm for determining which pager is to use as follows:

       1. Defer to $ENV{PAGER}
           Use the value of $ENV{PAGER} if it exists unless File::Which is available and the pager in
           $ENV{PAGER} is determined to be unavailable.

       2. Usual suspects
           Try the standard, hardcoded paths in "FILES".

       3. File::Which
           If File::Which is available check for "less" and more.

       4. more
           Set $ENV{PAGER} to "more"

       Steps 1, 3 and 4 rely upon $ENV{PATH}.

SEE ALSO
       IO::Pager::Buffered, IO::Pager::Unbuffered, IO::Pager::Page

       IO::Page, Tool::Less

AUTHOR
       Jerrad Pierce <jpierce@cpan.org>

       This module is forked from IO::Page 0.02 by Monte Mitzelfelt

LICENSE
       •   Thou shalt not claim ownership of unmodified materials.

       •   Thou shalt not claim whole ownership of modified materials.

       •   Thou shalt grant the indemnity of the provider of materials.

       •   Thou shalt use and dispense freely without other restrictions.



perl v5.12.5                                     2005-09-21                                     IO::Pager(3)