Probably a better way to do this, but here's one way:

Update So getpwnam is faster? Ok... 

my $username = "usernamehere";
print "Duplicate!\n" if getpwnam($username);

[download]
my $username = "user1";

while (<DATA>) {
    chomp;
    my @info = split ",";
    foreach (@info) {
        print "Duplicate!\n" if /\A\Q$username\E\z/
    }
}
        
__DATA__
user1
user2
user3
user4
user5,pass5,email5,ip5
user5,pass5,email5,ip5
user5,pass5,email5,ip5
user5,pass5,email5,ip5
user5,pass5,email5,ip5

[download]

In reply to Re: Re: Re: User Existance? by The Mad Hatter
in thread User Existance? by Anonymous Monk

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