Re: system() returns -1 with $SIG{CHLD}?

Are you forgetting that system returns a combination of the return status code together with the signal number with which the code was run ?

Probably worth investigating $! - as suggested in ...Return value of -1 indicates a failure to start the program or an error of the wait(2) system call (inspect $! for the reason)...

A user level that continues to overstate my experience :-))

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Re^2: system() returns -1 with $SIG{CHLD}? by ikegami (Patriarch) on Feb 11, 2009 at 19:48 UTC
When running the code I get -1 from `wait` and 0 from `system`. `$!` tells me `No child processes`. That makes sense since both `system` also does a `wait`. Why are you using `$SIG{CHLD}` with `system`? You shouldn't `wait` for a child launched using `system`.	[reply] [d/l] [select]
Re^3: system() returns -1 with $SIG{CHLD}? by cmv (Chaplain) on Feb 11, 2009 at 21:48 UTC
Why are you using $SIG{CHLD} with system? You shouldn't wait for a child launched using system. This was just a sample piece of code distilled down from a much larger perl program. In the big program, I'm running commands in the background, that take an arbitrary amount of time to complete. I don't want to be leaving any zombie processes around, so I used wait() with $SIG{CHLD} to mitigate this. Should I be doing something differently here, or should I be responsible for managing the handling of $SIG{CHLD} whenever I want to run a system() command? update: The zombies are left after forking a background process, not using system. I didn't make that clear	[reply]
Re^4: system() returns -1 with $SIG{CHLD}? by ikegami (Patriarch) on Feb 11, 2009 at 22:02 UTC
Should I be doing something differently here Yes, you shouldn't wait for a child started with `system`. I don't want to be leaving any zombie processes around `system` doesn't leave zombies cause it waits.	[reply] [d/l] [select]