I think this will do what you want. It creates a nice human-readable filename. It assumes no one changes the system time. It also assumes that it will not get called more than 1000 times a second. If that is a problem change the three in the last "%03d" in the sprintf to a larger number. 
use strict;
{
    my $lasttime;
    my $counter = 0;
    sub uniq_filename {
        my $time = time;
        if ($time == $lasttime) {
            $counter++;
        }
        else {
            $counter = 0;
            $lasttime = $time;
        }
        my @time = localtime($time);
        return sprintf ("%d%02d%02d%02d%02d%02d%03d", 
            $time[5]+1900, 
            $time[4]+1,
            $time[3],
            $time[2],
            $time[1],
            $time[0],
            $counter);
    }
}
for (1 .. 10) {
    print uniq_filename, "\n";
    select undef, undef, undef, .25;
}
__OUTPUT__
20020627092353000
20020627092354000
20020627092354001
20020627092354002
20020627092355000
20020627092355001
20020627092355002
20020627092355003
20020627092356000
20020627092356001

[download]

--

flounder

In reply to Re: Filenames based on timestamp by flounder99
in thread Filenames based on timestamp by Marcello

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