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


       File::Copy - Copy files or filehandles


               use File::Copy;

               copy("sourcefile","destinationfile") or die "Copy failed: $!";

               use File::Copy "cp";

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


       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

           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. If the second argument does not exist
           but the parent directory does exist, then it will be created.
           Trying to copy a file into a non-existent directory is an error.
           Trying to copy a file on top of itself is also an error.  "copy"
           will not overwrite read-only files.

           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

           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.

           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".

           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).

           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

           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.

           "rmscopy" is VMS specific and cannot be exported; it must be
           referenced by its full name, e.g.:

             File::Copy::rmscopy($from, $to) or die $!;

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


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


       Before calling copy() or move() on a filehandle, the caller should
       close or flush() the file to avoid writes being lost. Note that this is
       the case even for move(), because it may actually copy the file,
       depending on the OS-specific inplementation, and the underlying


       File::Copy was written by Aaron Sherman <> in 1995, and
       updated by Charles Bailey <> in 1996.

perl v5.26.1                      2017-07-18                   File::Copy(3pm)

perl 5.26.1 - Generated Sun Nov 5 09:09:05 CST 2017
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