Hello monks,

I need some advice with system calls. I have been researching for the past few days and have not been able to find what I'm looking for. I'm running a Perl CGI script from a webpage that needs to make some system calls. I'm running into a problem where no system calls will work at all. Not even a simple one such as "ls". Here's the important part of the code:

#! /usr/bin/perl -T
use strict;
use warnings;

$ENV{"PATH"} = "";
chdir "/home/user/";
chomp($update_location); # $update_location is:
                         # /home/user/test/update_test.pl
                         # it's retrieved from the database

my $cmd = sprintf("perl %s", $update_location);
system($cmd);
if ($? == -1) 
{
    logger("failed to execute: $!\n");
    # logger is a simple sub that appends whatever is passed
    # to an error.txt file
}
elsif ($? & 127) 
{
    logger("child died with signal coredump\n");
}
else
{
    my $sys_code = $? >> 8;
    logger("child exited with value $sys_code\n");
}

[download]

When I run the code above, my error.txt file says "failed to execute: Permission denied". When I comment out the chdir line, error.txt says "failed to execute: No such file or directory".
Whether or not I comment out the chdir line, if I try a simple system call such as:

system("ls");

it responds with "failed to execute: No such file or directory".
Permissions are
/home/ drwxr-xr-x
/home/user/ drwxr-xr-x
/home/user/test/ drwxr-xr-x
/home/user/test/update_test.pl -rwxr-xr-x
I already ran chmod +x on update_test.pl and am able to run it from a terminal.

Any ideas as to why the system calls won't work? Thank you for any advice you can give me!

In reply to System calls from CGI script by whitdan

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