in reply to Trouble getting CGI parameters

Your program does two things. It prints HTML output (a form you need to fill in) and then it appends to a data file. But you should only be appending to the data file after the form has been submitted. And your FORM tag has a very weird URL: "http://localhost/newuser.cgi?action=newuser?first?last" doesn't make a lot of sense. You probably just want "http://localhost/newuser.cgi".

Here is a simple program: 

#!/usr/bin/perl

use CGI;
use CGI::Carp qw( fatalsToBrowser );
use strict;
use warnings;

my $query = CGI->new;

# if we got here from a form being submitted,
# do the adduser() stuff
adduser($query) if $query->param;

print << "END_HTML";
<html>
<body>
<form method="post" action="thisprogram.cgi">
Username: <input type="text" name="user"><br>
First name: <input type="text" name="fname"><br>
Last name: <input type="text" name="lname"><br>
Password: <input type="password" name="pass"><br>
<input type="submit" value=" Add User ">
</form>
</body>
</html>
END_HTML


sub add_user {
  my ($q) = @_;
  open PASSWD, ">> $passwd_file"
    or die "can't append to $passwd_file: $!";
  print PASSWD join(":" =>
    $q->param('first'), $q->param('last'), $q->param('user'), $q->para
+m('pass')
  ), "\n";
  close PASSWD;
}

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Jeff japhy Pinyan, P.L., P.M., P.O.D, X.S.: Perl, regex, and perl hacker
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