Re^2: system() returns -1 with $SIG{CHLD}?

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.

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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]