if (param('deletepuser')) {
$deletepuser = param('deletepuser');
open (GUEST,"$private") ||die $!;
flock(GUEST, LOCK_SH);
@lines=<GUEST>;
flock(GUEST, LOCK_UN);
close(GUEST);

open (GUEST,">$private") || die $!;
flock(GUEST, LOCK_EX);
foreach (@lines) {
chomp;
if($_ ne ""){
($a,$b)=split(/__/,$_);
if($deletepuser ne $b){
print GUEST "$_\n";
}
}
}
flock(GUEST, LOCK_UN);
close(GUEST);

my $deletepuser = param('deletepuser');

if ($deletepuser) {
open (GUEST,"$private") ||die $!;
flock(GUEST, LOCK_SH);
my @lines = <GUEST>;
close(GUEST);

my @new_lines = grep { ! /^.*__$deletepuser$/ } @lines;

open (GUEST,">$private") || die $!;
flock(GUEST, LOCK_EX);
print GUEST @new_lines;
close(GUEST);
}

#!/perl/bin/perl

# Tested command line with text file on Windows XP
# This is perl, v5.6.1 built for MSWin32-x86-multi-thread
# (with 1 registered patch, see perl -V for more detail)
# Copyright 1987-2001, Larry Wall
# Binary build 635 provided by ActiveState Corp. http://www.ActiveState.com
# Built 15:34:21 Feb 4 2003

use strict;

my $private ="name_email.txt"; # Your line ommitted as I am on command line and not CGI imput.
# if (param('deletepuser')) {



my $deletepuser = lc("joe\@joe.com");
#my $deletepuser = lc("bob\@bob.com");
#my $deletepuser = lc("mary\@mary.com");
#my $deletepuser = lc("harry\@harry.com");



# Assign strict vars
my ($a,$b,$a2,$b2,$x,$y,$LINES,@LINES);
my ($LOCK_SH, $LOCK_UN, $LOCK_EX);



$LOCK_SH = 1;
$LOCK_EX = 2;
$LOCK_UN = 8;



# READ CURRENT FILE

open (GUEST,"$private") || die "Unable to open for input file $private: reason $! ";
flock(GUEST, $LOCK_SH);



$x=0;

while (<GUEST>) {
chomp; # remove new line character
($a,$b)=split(/\_\_/,$_); # split the name email pairs
$a2 = lc($a); # LOWER CASE for compare
$b2 = lc($b); # LOWER CASE for compare




if(($deletepuser ne $a2) and ($deletepuser ne $b2)){
$LINES[$x] = "$a\_\_$b"; # use the origional case text
$x++;
} # end of if(($deletepuser ne ... loop



} # end of while (<GUEST>) loop

flock(GUEST, $LOCK_UN);
close(GUEST);



# Write new file without duplicate user from $deletepuser


open (NEWGUEST,">$private") || die "Unable to open for output file $private: reason $! ";
flock(NEWGUEST, $LOCK_EX);

for ($y=0; $y<$x; $y++) {
print NEWGUEST "$LINES[$y]\n";
}

flock(NEWGUEST, $LOCK_UN);
close(NEWGUEST);



# } end of YOUR if (param('deletepuser')) ... loop here ?

# ======================================================

# Name_email.txt contains without first pound character:

#bob__bob@bob.com
#mary__mary@mary.com
#harry__harry@harry.com
#joe@joe.com__JOE@JOE.com
#joe@joe.com__JOE@Joe.com
#joe@joe.com__joe@JoE.coM
#bob__bob@bob.com
#mary__mary@mary.com
#harry__harry@harry.com

Thanks cornball

my $deletepuser = param('deletepuser');

if ($deletepuser) {
open (GUEST,"$private") ||die $!;
flock(GUEST, LOCK_SH);
my @lines = <GUEST>;
close(GUEST);

foreach (@lines) {
if ($_ =~ /^.*__$deletepuser$/) { print "Match...\n<BR>"; }
}

my @new_lines = grep { ! /^.*__$deletepuser$/ } @lines;

open (GUEST,">$private") || die $!;
flock(GUEST, LOCK_EX);
print GUEST @new_lines;
close(GUEST);
}