If myprog.exe can not be run, system(...) returns on my platform 256 (which is exit code 1, no child-error), and, as you point out, sets $! to some error code.

You have a broken Perl if that's true.

If myprog can not be run, system sets $? to -1 and sets the error in $!.

If a shell command cannot be run, system sets $? to something other than -1 (since the shell was successfully executed) and $! contains no meaningful information. The shell cannot possibly change the parent's errno.

In reply to Re^3: system and $? by ikegami
in thread system and $? by rovf

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