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question about system and popen in C

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# 1  
Old 03-17-2011
question about system and popen in C
in man system it talks about SIGCHLD will be blocked, and SIGINT and SIGQUIT will be ignored.

Does this signal stuff also happen in popen command?
(even though man popen says nothing about signals)

also if I am not using wait(&status) and I am using waitpid(pid, NULL, 0)

how would WEXITSTATUS(status) work since i am not using the status variable? if it doesnt how do i get the exit code of the execl process that ran from the child process
# 2  
Old 03-17-2011
Quote:
Originally Posted by omega666
in man system it talks about SIGCHLD will be blocked, and SIGINT and SIGQUIT will be ignored.

Does this signal stuff also happen in popen command?
(even though man popen says nothing about signals)
I honestly don't know. I'd assume not if it says nothing about it but different systems may do different things.
Quote:
also if I am not using wait(&status) and I am using waitpid(pid, NULL, 0)

how would WEXITSTATUS(status) work since i am not using the status variable? if it doesnt how do i get the exit code of the execl process that ran from the child process
man waidpid will tell you how to get the status variable out of it: waitpid(pid, &status, 0);
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