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Top Forums Programming question about system and popen in C Post 302505810 by omega666 on Thursday 17th of March 2011 06:12:03 PM
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
 

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explain_popen_or_die(3) 				     Library Functions Manual					   explain_popen_or_die(3)

NAME
explain_popen_or_die - process I/O and report errors SYNOPSIS
#include <libexplain/popen.h> FILE *explain_popen_or_die(const char *command, const char *flags); DESCRIPTION
The explain_popen_or_die function is used to call the popen(3) system call. On failure an explanation will be printed to stderr, obtained from explain_popen(3), and then the process terminates by calling exit(EXIT_FAILURE). This function is intended to be used in a fashion similar to the following example: FILE *fp = explain_popen_or_die(command, flags); command The command, exactly as to be passed to the popen(3) system call. flags The flags, exactly as to be passed to the popen(3) system call. Returns: This function only returns on success, see popen(3) for more information. On failure, prints an explanation and exits. SEE ALSO
popen(3) process I/O explain_popen(3) explain popen(3) errors exit(2) terminate the calling process COPYRIGHT
libexplain version 0.52 Copyright (C) 2009 Peter Miller explain_popen_or_die(3)
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