In my crash course Perl lesson of porting a decade plus old application running on a Unix server to run on a Windows 2003 server, I have made extensive use of Google to resolve and learn about features of the code with which I was unfamiliar.

This has generally worked well for me, but is failing in this one regard. In several places in the code there is a reference to $?. It is almost always after a system call using the open() function, usually to SQL*Plus in this application's case. It seems to be involved in exception handling as it is generally used in code such as this:

$v_error = $?/256; 

if ($v_error) {...}

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So can somebody kindly point me to or provide a basic understanding on what $? is actually referencing I would really appreciate it. What does this actually do under the hood. I have found that searching Google for a '?' to be rather fruitless.

Thank You

In reply to $? What does this reference? by iskinner

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