File::Copy - Copy files or filehandles
use File::Copy;
copy("file1","file2");
copy("Copy.pm",\*STDOUT);'
move("/dev1/fileA","/dev2/fileB");
use POSIX;
use File::Copy cp;
$n=FileHandle->new("/dev/null","r");
cp($n,"x");'
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.
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).
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 behavour 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 wil 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.
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. For
VMS systems, this calls the rmscopy
routine (see below). For
OS/2 systems, this calls the syscopy
XSUB directly.
syscopy is defined (VMS and OS/2)
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).
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.
All functions return 1 on success, 0 on failure. $! will be set if an error was encountered.
File::Copy was written by Aaron Sherman <ajs@ajs.com> in 1995, and updated by Charles Bailey <bailey@genetics.upenn.edu> in 1996.
If rather than formatting bugs, you encounter substantive content errors in these documents, such as mistakes in the explanations or code, please use the perlbug utility included with the Perl distribution.