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File::Copy(3pm)                       Perl Programmers Reference Guide                       File::Copy(3pm)



NAME
       File::Copy - Copy files or filehandles

SYNOPSIS
               use File::Copy;

               copy("file1","file2") or die "Copy failed: $!";
               copy("Copy.pm",\*STDOUT);
               move("/dev1/fileA","/dev2/fileB");

               use File::Copy "cp";

               $n = FileHandle->new("/a/file","r");
               cp($n,"x");

DESCRIPTION
       The File::Copy module provides two basic functions, "copy" and "move", which are useful for getting
       the contents of a file from one place to another.

       copy
           The "copy" function takes two parameters: a file to copy from and a file to copy to. Either
           argument may be a string, a FileHandle reference or a FileHandle glob. Obviously, if the first
           argument is a filehandle of some sort, it will be read from, and if it is a file name it will be
           opened for reading. Likewise, the second argument will be written to (and created if need be).
           Trying to copy a file on top of itself is a fatal error.

           If the destination (second argument) already exists and is a directory, and the source (first
           argument) is not a filehandle, then the source file will be copied into the directory specified
           by the destination, using the same base name as the source file.  It's a failure to have a
           filehandle as the source when the destination is a directory.

           Note that passing in files as handles instead of names may lead to loss of information on some
           operating systems; it is recommended that you use file names whenever possible.  Files are opened
           in binary mode where applicable.  To get a consistent behaviour when copying from a filehandle to
           a file, use "binmode" on the filehandle.

           An optional third parameter can be used to specify the buffer size used for copying. This is the
           number of bytes from the first file, that will be held in memory at any given time, before being
           written to the second file. The default buffer size depends upon the file, but will generally be
           the whole file (up to 2MB), or 1k for filehandles that do not reference files (eg. sockets).

           You may use the syntax "use File::Copy "cp"" to get at the "cp" alias for this function. The
           syntax is exactly the same.  The behavior is nearly the same as well: as of version 2.15, <cp>
           will preserve the source file's permission bits like the shell utility cp(1) would do, while
           "copy" uses the default permissions for the target file (which may depend on the process'
           "umask", file ownership, inherited ACLs, etc.).  If an error occurs in setting permissions, "cp"
           will return 0, regardless of whether the file was successfully copied.

       move
           The "move" function also takes two parameters: the current name and the intended name of the file
           to be moved.  If the destination already exists and is a directory, and the source is not a
           directory, then the source file will be renamed into the directory specified by the destination.

           If possible, move() will simply rename the file.  Otherwise, it copies the file to the new
           location and deletes the original.  If an error occurs during this copy-and-delete process, you
           may be left with a (possibly partial) copy of the file under the destination name.

           You may use the "mv" alias for this function in the same way that you may use the <cp> alias for
           "copy".

       syscopy
           File::Copy also provides the "syscopy" routine, which copies the file specified in the first
           parameter to the file specified in the second parameter, preserving OS-specific attributes and
           file structure.  For Unix systems, this is equivalent to the simple "copy" routine, which doesn't
           preserve OS-specific attributes.  For VMS systems, this calls the "rmscopy" routine (see below).
           For OS/2 systems, this calls the "syscopy" XSUB directly. For Win32 systems, this calls
           "Win32::CopyFile".

           Special behaviour if "syscopy" is defined (OS/2, VMS and Win32):

           If both arguments to "copy" are not file handles, then "copy" will perform a "system copy" of the
           input file to a new output file, in order to preserve file attributes, indexed file structure,
           etc.  The buffer size parameter is ignored.  If either argument to "copy" is a handle to an
           opened file, then data is copied using Perl operators, and no effort is made to preserve file
           attributes or record structure.

           The system copy routine may also be called directly under VMS and OS/2 as "File::Copy::syscopy"
           (or under VMS as "File::Copy::rmscopy", which is the routine that does the actual work for
           syscopy).

       rmscopy($from,$to[,$date_flag])
           The first and second arguments may be strings, typeglobs, typeglob references, or objects
           inheriting from IO::Handle; they are used in all cases to obtain the filespec of the input and
           output files, respectively.  The name and type of the input file are used as defaults for the
           output file, if necessary.

           A new version of the output file is always created, which inherits the structure and RMS
           attributes of the input file, except for owner and protections (and possibly timestamps; see
           below).  All data from the input file is copied to the output file; if either of the first two
           parameters to "rmscopy" is a file handle, its position is unchanged.  (Note that this means a
           file handle pointing to the output file will be associated with an old version of that file after
           "rmscopy" returns, not the newly created version.)

           The third parameter is an integer flag, which tells "rmscopy" how to handle timestamps.  If it is
           < 0, none of the input file's timestamps are propagated to the output file.  If it is > 0, then
           it is interpreted as a bitmask: if bit 0 (the LSB) is set, then timestamps other than the
           revision date are propagated; if bit 1 is set, the revision date is propagated.  If the third
           parameter to "rmscopy" is 0, then it behaves much like the DCL COPY command: if the name or type
           of the output file was explicitly specified, then no timestamps are propagated, but if they were
           taken implicitly from the input filespec, then all timestamps other than the revision date are
           propagated.  If this parameter is not supplied, it defaults to 0.

           Like "copy", "rmscopy" returns 1 on success.  If an error occurs, it sets $!, deletes the output
           file, and returns 0.

RETURN
       All functions return 1 on success, 0 on failure.  $! will be set if an error was encountered.

AUTHOR
       File::Copy was written by Aaron Sherman <ajs@ajs.com> in 1995, and updated by Charles Bailey
       <bailey@newman.upenn.edu> in 1996.



perl v5.16.2                                     2012-10-25                                  File::Copy(3pm)