My friend doesn't have SSH access to his crappy hosted web server, and he doesn't know which Perl modules are installed. So...I wrote a simple CGI script that I thought would allow him to check for installed modules:
#!/usr/bin/perl

use strict;

use CGI qw/:standard/;
use CGI::Carp 'fatalsToBrowser';

my $module = param('module');
my $result;

checkForModule();
showPage();

sub checkForModule
{
    $result = `/usr/bin/perl -M$module -e 1`;
}

sub showPage
{
    print
    header,
    start_html({-onload => "document.moduleForm.module.focus()", title
+ => "Module Checker"}),
    qq(
    <br /><br />
    
    $result $module
    
    <br /><br />
    <form method="post" action="have.pl" name="moduleForm">
        <input type="text" name="module" id="module" maxlength="50">
        <input type="submit" value="Check for Module" name="submitButt
+on" id="submitButton">
    </form>
    ),
    end_html();
}

[download]

However, the $result scalar never has a value. Why not?

In reply to Calling perl from CGI by PerlRob

Title:
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