Hi Monks, I'm currently trying to write some perl to:

read input
validate that the input is alpha-numeric, a hyphen or a space
strip out "malicious characters"
return the sanitised input

Whilst I seem to be able to match any input that is not "safe", I'm having problems with the substitution. After playing around with it on and off for the last 2 days, I'm not managing to nail it. Can anyone tell me what I'm missing please? (code is part of a larger script, hence the sub, I'm about 3 days into perl so apologies if my code/layout sucks!)

Thanks in advance. 
#!/usr/bin/perl

#supply test strings on the command line for ease
$test1 = shift(@ARGV);

sub validate_text
{
        if ( $test1 =~ m/^[A-Za-z0-9\-\ ]+$/ )
        {
                print "Text clean\n";
                return ($test1);
        } else {
                $errorstring = "Funny business with variables occuring
+, have attempted to fix";

                print "$errorstring\n";
                print "dollartest before fixing = $test1\n";

                $test1 =~ s/^[^A-Za-z\-\ ]+$//g;
                print "dollartest after fixing = $test1\n";

                return ($test1);
        }
}
$validated = &validate_text;

print "the validated text is: $validated\n";

[download]

The output from the script follows:
[lowprivuser@localhost testing]$ perl regexp-check2.pl abcd\"efg

 Funny business with variables occuring, have attempted to fix
dollartest before fixing = abcd"efg
dollartest after fixing = abcd"efg
the validated text is: abcd"efg

[lowprivuser@localhost testing]$ perl regexp-check2.pl abcdefg1

Text clean

the validated text is: abcdefg1

[lowprivuser@localhost testing]$

[download]

In reply to Inverse regexes for input validation by Anonymous Monk

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