The while test on the value of days is made after the conversion to seconds is done so when you enter q you are trying to convert it to seconds. you could do a few things, here is one that keeps a while loop... 

#!/usr/local/bin/perl -w
use strict;

while (1) {
    print
"Please enter a single positive integer that represents a number of da
+ys, that you wish to convert into seconds. ,(enter q to quit): ";

    chomp (my $days = <STDIN>);
    $days =~ s/\+//;    # allow them to enter +12

    if ($days eq "q") {
        last;
    } elsif (($days =~ /[^\d]/) or ($days eq "")) {
        # days contains an non digit character or is empty
        print "\n!!! You must enter a positive integer.\n\n";
    } else {
        my $seconds = $days * 86400;
        my $plural = ($days == 1) ? '' : 's';
        print "\n$days day$plural = $seconds seconds.\n\n";
    }
}

print "Goodbye\!\n\n";

[download]

update to catch entry of 0

Change the elsif check to this if you want to prevent them from entering zero days 
    } elsif (($days =~ /[^\d]/) or (not $days)) {

[download]

Cheers,
R.

In reply to Re: String/Numeric Manipulation by Random_Walk
in thread String/Numeric Manipulation by Ms. T.

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