You can find this documented in perlvar along with all the other punctuation variables. The beginning of the description for $? is:

The status returned by the last pipe close, backtick (``) command, successful call to wait() or waitpid(), or from the system() operator. This is just the 16-bit status word returned by the traditional Unix wait() system call (or else is made up to look like it).

In reply to Re: $? What does this reference? by kyle
in thread $? What does this reference? by iskinner

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