unixdev.net


Switch to SpeakEasy.net DSL

The Modular Manual Browser

Home Page
Manual: (OpenBSD-3.6)
Page:
Section:
Apropos / Subsearch:
optional field



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


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.

       o   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.

           Note that passing in files as handles instead of names
           may lead to loss of information on some operating sys-
           tems; it is recommended that you use file names when-
           ever possible.  Files are opened in binary mode where
           applicable.  To get a consistent behaviour when copy-
           ing 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.

       o   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



perl v5.8.5                 2002-11-06                          1





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


           directory, and the source is not a directory, then the
           source file will be renamed into the directory speci-
           fied by the destination.

           If possible, move() will simply rename the file.  Oth-
           erwise, 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 (pos-
           sibly 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-spe-
       cific 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".

       On Mac OS (Classic), "syscopy" calls "Mac::MoreFiles::FSp-
       FileCopy", if available.

       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, type-
           globs, 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



perl v5.8.5                 2002-11-06                          2





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


           input file, except for owner and protections (and pos-
           sibly 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 asso-
           ciated 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 times-
           tamps 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 times-
           tamps 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.

NOTES
       o   On Mac OS (Classic), the path separator is ':', not
           '/', and the current directory is denoted as ':', not
           '.'. You should be careful about specifying relative
           pathnames. While a full path always begins with a vol-
           ume name, a relative pathname should always begin with
           a ':'.  If specifying a volume name only, a trailing
           ':' is required.

           E.g.

             copy("file1", "tmp");        # creates the file 'tmp' in the current directory
             copy("file1", ":tmp:");      # creates :tmp:file1
             copy("file1", ":tmp");       # same as above
             copy("file1", "tmp");        # same as above, if 'tmp' is a directory (but don't do
                                          # that, since it may cause confusion, see example #1)
             copy("file1", "tmp:file1");  # error, since 'tmp:' is not a volume
             copy("file1", ":tmp:file1"); # ok, partial path
             copy("file1", "DataHD:");    # creates DataHD:file1

             move("MacintoshHD:fileA", "DataHD:fileB"); # moves (don't copies) files from one
                                                        # volume to another



perl v5.8.5                 2002-11-06                          3





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


AUTHOR
       File::Copy was written by Aaron Sherman &lt;ajs@ajs.com&gt; in
       1995, and updated by Charles Bailey &lt;bailey@new-
       man.upenn.edu&gt; in 1996.





















































perl v5.8.5                 2002-11-06                          4