in reply to file::find

The first argument to find() is a code reference (like a pointer to a subroutine) and the rest of the arguments are the directories where to search. For each file in those directories, the subroutine is called with the file name as its argument. The subroutine is responsible for checking whatever you want to check, and for doing whatever you want to do. So for example, if you want to print all files ending in .tex under your 'Docs' directory, you could do something like this: 
use File::Find;
find( sub { 
    /\.tex$/ && print "$File::Find::name\n" },
  'Docs');

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Note that I used an anonymous subroutine here. The above could have been written as follows: 
find(\&wanted, 'Docs');
sub wanted {
  /\.tex$/ && print "$File::Find::name\n";
}

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A good way to learn is to use the find2perl program, which should be included in your Perl distribution. It takes the same arguments as the find command, and spits out a Perl program that uses the File::Find module to do the same thing. By looking at the generated programs you can learn a lot about how to use the module.

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RE: Re: file::find
by btrott (Parson) on May 01, 2000 at 21:13 UTC
    Actually, no--the filename isn't supplied as the argument to your subroutine. There aren't any arguments, in fact. (Actually, if you peek at @_ in your wanted function, you *will* see arguments. But they're not actually supplied as arguments to your subroutine: they're the arguments to File::Find's finddir subroutine, which calls your wanted sub as &$wanted, which makes its @_ visible to your subroutine.) More in perlsub.

    But that's getting off track. Anyway, what File::Find does is sets some package variables and $_ to the file name, the directory, and a combination of those two. From the docs: 

        $File::Find::dir contains the current
    directory name, and $_ the current filename within
    that directory. $File::Find::name contains
    "$File::Find::dir/$_".  You are chdir()'d to
    $File::Find::dir when the function is called.
    The function may set $File::Find::prune to prune
    the tree.

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