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NAME
    File::Remote - Read/write/edit remote files transparently

SYNOPSIS
       #
       # Two ways to use File::Remote
       #
       # First, the function-based style. Here, we can use the 
       # special :replace tag to overload Perl builtins!
       #
       use File::Remote qw(:replace);       # special :replace tag

       # read from a remote file
       open(REMOTE, "host:/remote/file") or die $!;
       print while (<REMOTE>);
       close(REMOTE);

       # writing a local file still works!
       open(LOCAL, ">>/local/file");
       print LOCAL "This is a new line.\n";
       close(LOCAL); 
 
       mkdir("host:/remote/dir", 0755);
       unlink("host:/remote/file");
       unlink("/local/file");               # still works too!
       symlink("host:/remote/src", "host:/remote/dest");

       chown("root", "other", "host:/remote/dir/file");
       chmod(0600, "host:/remote/dir/file");

       #  
       # Next, the object-oriented style, if you don't want to
       # mess with the builtins.
       #
       use File::Remote;
       my $remote = new File::Remote;
 
       # Standard filehandles
       $remote->open(FILE, ">>host:/remote/file") or die $!;
       print FILE "Here's a line that's added.\n";
       $remote->close(FILE);
 
       # Create a new file and change its permissions
       $remote->mkdir("host:/remote/dir");
       $remote->touch("host:/remote/dir/file");
 
       # Move files around
       $remote->copy("/local/file", "host:/remote/file") or warn $!;
       $remote->move("host:/remote/file", "/local/file");
 
       # Read and write whole files
       my @file = $remote->readfile("host:/remote/file");
       $remote->writefile("/local/file", @file);
 
       # Backup a file with a suffix
       $remote->backup("host:/remote/oldfile", "save");
 
       # Use secure connection methods
       my $secure = new File::Remote (rsh => "/usr/local/bin/ssh",
                                      rcp => "/usr/local/bin/scp");
       $secure->unlink("/local/file");
       $secure->rmdir("host:/remote/dir");

DESCRIPTION
    This module takes care of dealing with files regardless of whether
    they're local or remote. It allows you to create and edit files without
    having to worry about their physical location on the network. If a file
    passed into a function is of the form "host:/path/to/file", then
    "File::Remote" uses rsh/rcp (or ssh/scp, depending on how you configure
    it) to edit the file remotely. Otherwise, it assumes the file is local
    and passes calls directly through to Perl's core functions.

    The nice thing about this module is that you can use it for *all* your
    file calls, since it handles both remote and local files transparently.
    This means you don't have to put a whole bunch of checks for remote
    files in your code. Plus, if you use the function-oriented interface
    along with the ":replace" tag, you can actually redefine the Perl
    builtin file functions. This means that your existing Perl scripts can
    automatically handle remote files with no re-engineering(!).

    There are two ways to program with "File::Remote", an object-oriented
    style and a function-oriented style. Both methods work equally well,
    it's just a matter of taste. One advantage of the object-oriented method
    is that this allows you to read and write from different servers using
    different methods (eg, rsh vs. ssh) simultaneously:

       # Object-oriented method
       use File::Remote;
       my $remote = new File::Remote;
       my $secure = new File::Remote (rsh => "/bin/ssh", rcp => "/bin/scp");

       # Securely copy, write, and remove a file in one swoop...
       $remote->open(LOCAL, "/local/file") or die "Open failed: $!\n";
       $secure->open(REMOTE, "host:/remote/file") or die "Open failed: $!\n";
       print REMOTE "$_" while (<LOCAL>);

       $remote->close(LOCAL);
       $secure->close(REMOTE);

       # And let's move some files around securely
       $secure->move("/local/file", "host:/remote/file");
       $secure->copy("host:/remote/file", "/local/file");

    To use the function-oriented interface, you must import the special tag
    called ":replace" which will actually replace the Perl builtin
    functions:

       # Replace Perl's file methods with File::Remote's
       use File::Remote qw(:replace);

       open(FILE, ">host:/remote/file") or die "Open failed: $!\n";
       print FILE "Hello, world!\n";
       close(FILE) or die "Close failed: $!\n";

       mkdir("/local/new/dir", "2775");
       mkdir("host:/remote/new/dir");
       chown("root", "other", "/local/new/dir");
       unlink("host:/remote/file");

    This is pretty neat; since "File::Remote" will pass calls to local files
    straight through to Perl's core functions, you'll be able to do all this
    "transparently" and not care about the locations of the files. Plus,
    this has the big advantage of making your existing Perl scripts capable
    of dealing with remote files without having to rewrite any code.

    Because the names for the "File::Remote" methods clash with the Perl
    builtins, if you use the function-oriented style with the ":standard"
    tag there is an extra 'r' added to the front of the function names.
    Thus, "<$remote-"open>> becomes 'ropen' in the ":standard"
    function-oriented version:

       # Function-oriented method
       use File::Remote qw(:standard);      # use standard function names
       setrsh("/share/bin/ssh");
       setrcp("/share/bin/scp");

       # same functionality, but there's an "r" prefix
       ropen(FILE, "host:/remote/file") or die "Open failed: $!\n";
       print while (<FILE>);
       rclose(FILE) or die "Close failed: $!\n";

       runlink("host:/remote/file");
       rmkdir("host:/remote/dir");
       rchmod("0700", "host:/remote/dir");

    That's kinda nasty, though. I recommend you use the ":replace" tag,
    personally.

FUNCTIONS
    Below are each of the functions you can make use of with "File::Remote".
    Remember, for the function-oriented style, unless you use the ":replace"
    tag you'll have to add an extra 'r' to the start of each function name.
    For all functions, the file arg can be either local or remote.

  new(opt => val, opt => val)

    This is the main constructor when you're using the object-oriented
    method of calling. You only need to use this if you're using the
    object-oriented calling form. You can pass it three arguments which
    change how it works:

       rsh  -  path to your rsh or ssh program
       rcp  -  path to your rcp or scp program
       tmp  -  path to your tmp directory

    So, for example:

       use File::Remote;
       my $secure = File::Remote->new(rsh => '/usr/local/bin/ssh',
                                      rcp => '/usr/local/bin/scp',
                                      tmp => '/var/run');
       $secure->copy($src, $dest);

    The above would setup your "$secure" object so that calls to methods on
    it would use ssh and scp for connections.

  setrsh(prog) ; setrcp(prog) ; settmp(dir)

    These perform the equivalent functionality to setting the above flags,
    for use in the function-oriented method of calling. So, if you were to
    decide you didn't want to use the OO method, but instead wanted to use
    the drop-in replacement function method (which I prefer):