reading all files in a dir

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

I searched the other SOPWs and was linked to the main thread here for READDIR and OPENDIR but I can't get the example to work. I want to slurp up every file in a directory (in reality I want to slurp only .jpgs but there's only one type of file in the directory anyway). The script is run from within the same directory as the one I want to read from, which is why my $dir = "."

No errors, it's just not printing anything out. Any idea why?

#!/usr/bin/perl

use warnings;
use strict;

my $dir = ".";

    opendir(DIR, $dir) || die "can't opendir $dir: $!";
    my @dots = grep { /^\./ } readdir(DIR);
    closedir DIR;


print join("\n", @dots);
[download]

Comment on reading all files in a dir Download Code

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Re: reading all files in a dir by jeffa (Bishop) on Aug 25, 2006 at 18:11 UTC
How about using a glob instead? `my @jpg = <.jpg>;` [download] Or maybe Find::File::Rule? `my @file = File::Find::Rule ->file() ->name( '.jpg' ) ->in( '.' ) ;` [download] jeffa L-LL-L--L-LL-L--L-LL-L-- -R--R-RR-R--R-RR-R--R-RR B--B--B--B--B--B--B--B-- H---H---H---H---H---H--- (the triplet paradiddle with high-hat)	[reply] [d/l] [select]
Re: reading all files in a dir by friedo (Prior) on Aug 25, 2006 at 18:19 UTC
`my @dots = grep { /^\./ } readdir(DIR);` [download] That finds all the files beginning with a . in your directory. You forgot to invert the regex for your grep. What you probably want is: `my @not_dots = grep { !/^\./ } readdir(DIR);` [download] Then `@not_dots` will contain all the non-dotfiles.	[reply] [d/l] [select]
Re: reading all files in a dir by jwkrahn (Abbot) on Aug 25, 2006 at 18:21 UTC
my @dots = grep { /^\./ } readdir(DIR); Your regular expression says to match only file names that begin with a period, you probably want: `my @dots = grep { -f } readdir(DIR);` [download] Which will match only "plain" files or: `my @dots = grep { /\.jpg\z/i } readdir(DIR);` [download] Which will match only JPEG files.	[reply] [d/l] [select]
Re: reading all files in a dir by swampyankee (Parson) on Aug 25, 2006 at 18:27 UTC
If you look at your grep statement, you're only selecting files that start with a "dot". Ok; this is well and good. Indeed, it works just as I would expect (I run it and get this: `. ..` [download] with no new line on the last line of output) I'm thinking this is the opposite of what you want, which is probably the files which don't start with a period, in which case your `grep` statement would look like this: `my @dots = grep { ! /^\./} readdir(DIR);` [download] which will take out files which start with a period instead of the files which don't. As an (possibly preferable) alternative, you could use this: `my @dots = glob(""); # adjust argument to glob as needed` [download] Most of the time, I tend to prefer `glob`, mostly because I'm lazy (it saves a lot of typing). The exception is when I've got to deal with Windows (which is most of the time), where I find that `glob` seems to get confused with filenames containing blanks (yeah, I could escape them). emc Only two things are infinite, the universe and human stupidity, and I'm not sure about the former.* Albert Einstein	[reply] [d/l] [select]