Getting a list of files in a directory sorted by date

[slloyd]

How would I get a list of files in a directory, sorted by date? Will the following code insure that the oldest file is first in the list?

opendir(DIR,$logdir);
my @cfiles=grep(/\w/,readdir(DIR));
close(DIR);

[Ovid]

I'm not sure how expensive pulling the date for a file is, but assuming it's reasonably exensive and you have a lot of files, then a Schwartzian Transform is a natural way to go.

opendir DIR, $logdir or die "Cannot open $logdir: $!";

my @cfiles = map  { $_->[1] }
             sort { $a->[0] <=> $b->[0] }
             map  { [ -M $_, $_ ] }
             grep { /\w/ } 
             readdir DIR;

Update: Fixed the typo that slloyd and philcrow pointed out (/w/ should have been /\w/).

[philcrow]

The grep expression here looks funny. It seems to say the file must contain a w. Perhaps you meant:

grep { /\w/ }

Phil

[slloyd]

Your code example does not return any files.

[Ovid]

Works fine on my box. Did you run it?

[explorer]

opendir(DIR,$logdir);
foreach( readdir(DIR) ) {
    next unless /\w/;
    $date{ -M $_ } = $_;  # Store modification's time
}
closedir DIR;
foreach ( sort { $a <=> $b } keys %date ) {
    print $date{$_}      # Show ordered files
}

[Ovid]

What happens when you have two files with the same mtime?

[davidrw]

see Open files by date created for the same question and lots of very good replies & information

[salva]

use Sort::Key qw(nkeysort);

opendir my $dh, "..." or die;
my @sorted = nkeysort { -M } grep /\w/, readdir $dh;

[kwaping]

This isn't the most elegant or Perlish solution, but you could just `ls -rt`.