uvnew has asked for the wisdom of the Perl Monks concerning the following question:

Hi Monks. I need to loop through all files inside a folder (one by one), and just get all file names, to use the names somewhere else. So if the library contains: file1, file2, file3 then I would want to have this pseudocode: for all files in folder: { temp_name = get_current_file_name(); function(temp_name); } Thanks in advance!

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Re: getting files names
by jettero (Monsignor) on Apr 27, 2007 at 13:12 UTC

    my @filez = <folder/*>;? Or is there more to this that I'm missing?

    On the other hand... from your "pseudo-code," you might want an iterator perhaps? 

    sub get_filez {
  my @filez = <folder/*>;
  return sub {
     return shift @filez;
  }
}

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    -Paul

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Re: getting files names
by derby (Abbot) on Apr 27, 2007 at 13:15 UTC
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Re: getting files names
by swampyankee (Parson) on Apr 27, 2007 at 17:13 UTC

    Use glob or opendir and readdir to get a list of filenames, then loop through the list.

    For example, 

    my $dir = '.'
my @list = glob($dir . '/*'); # <- amended per merlyn's response

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    or
    my $dir = '.';
opendir(my $dh, $dir) or die "Could not open $dir because $!\n;
@list = readdir($dh);

closedir($dh);

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    will return a list of files in the current working directory. My preference is to use glob for this sort of thing. Usually, the number of files in a directory will be small (no more than a few thousand), so storing the names in an array should not be a problem. You may want to filter @list, so that it contains only the type of file you want, but this is easy using grep. Glob can process wildcards, so @list could be restricted by something like 
    @list = glob($dir .'/A*');

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    Alternatively, you could call readdir in a scalar context, and process the files one at a time. The code for this would look something like: 
    my $dir = '.';
opendir(my $dh, $dir) or die "Could not open $dir because $!\n;
while(readdir($dh)){
   # do stuff to $_
}
closedir($dh);

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    As I said, since the number of files in a folder tends to be fairly small, I prefer to use glob, possibly in conjunction with grep to get a list of file names, and then loop through that list.

    Corrected call to glob; see merlyn's response.

    emc

    Insisting on perfect safety is for people who don't have the balls to live in the real world.

    —Mary Shafer, NASA Dryden Flight Research Center
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      You said: 
      my $dir = '.'
my @list = glob($dir);

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      But that's not going to work. Glob wants a glob pattern. As ".", there's not much of a pattern there. See some of the other answers in this thread.

      -- Randal L. Schwartz, Perl hacker

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Re: getting files names
by cengineer (Pilgrim) on Apr 27, 2007 at 14:17 UTC
    Hope this helps 
    my $files = dirlist($someDirectory);

foreach my $fileInDirectory (@$files) {

dosomething($fileInDirectory);

}


sub dirlist {
        my $dir = shift;
        my @filelist;
        opendir(DIR, $dir) or die "can't opendir $dir: $!";
        while (defined(my $file = readdir(DIR))) {

                # Skip "." and ".."
                next if ($file =~ /^\.\.?$/);
                push(@filelist, $file);

        }
        closedir(DIR);
        return \@filelist;
}

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Re: getting files names
by akho (Hermit) on Apr 27, 2007 at 21:26 UTC
    ummm… 

    function($_) foreach (glob "$folder/*");

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