Ronen Kfir wrote:
>
> I need to delete oldest modified file in a directory. I find this file with this:
>
> my $oldest= printf "%s\n", (sort{ (-M $b) <=> (-M$a) } glob("v:\*"));
> print $oldest;
>
> unlink "$oldest";
>
> What I get in response is:
>
> oldest_filename
> 1
>
> File is not deleted.
>
> How would I do it?
As you have observed, printf returns true if it worked (or false if it
didn't.) You
could do it like this:
my ( $oldest ) = sort { (-M $b) <=> (-M $a) } glob "v:\*";
unlink $oldest or warn "Cannot delete $oldest: $!";
Or like this:
my $oldest = ( sort { (-M $b) <=> (-M $a) } glob "v:\*" )[ 0 ];
unlink $oldest or warn "Cannot delete $oldest: $!";
But both of those methods use an inefficient sort because you are
stat()ing each
file more than once. Here are two methods that only stat()s each file
once.
my ( $oldest ) = map $_->[ 0 ],
sort { $b->[ 1 ] <=> $a->[ 1 ] }
map [ $_, -M ],
glob "v:\*";
unlink $oldest or warn "Cannot delete $oldest: $!";
This is the most efficient as it only stat()s each file once and it
doesn't have to sort.
my $oldest = [ '', 0 ];
for my $file ( glob "v:\*" ) {
my $date = -M $file;
$oldest = [ $file, $date ] if $oldest->[ 1 ] < $date;
}
unlink $oldest->[ 0 ] or warn "Cannot delete $oldest->[0]: $!";
John
--
use Perl;
program
fulfillment
--
To unsubscribe, e-mail: [EMAIL PROTECTED]
For additional commands, e-mail: [EMAIL PROTECTED]
