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Full Discussion: signal handler for SIGCHLD
Top Forums Programming signal handler for SIGCHLD Post 76769 by blowtorch on Thursday 30th of June 2005 11:56:52 AM
Old 06-30-2005
jens,

Welcome to the UNIX forums!

To answer your questions:
1. sigaction and sigprocmask are just the syscalls that you need. sigaction will replace your signal syscall. Check the man pages for details.
2. Yes, since the child has already exited, the wait syscall will just reap the child and go on.

Moderators,
Could this be moved to the c programming forums?
 

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PTHREAD_ATFORK(3)					   BSD Library Functions Manual 					 PTHREAD_ATFORK(3)

NAME
pthread_atfork -- register handlers to be called before and after fork() SYNOPSIS
#include <pthread.h> int pthread_atfork(void (*prepare)(void), void (*parent)(void), void (*child)(void)); DESCRIPTION
The pthread_atfork() function is used to register functions to be called before and after fork(). The prepare handler is called before fork(), while the parent and child handlers are called after fork() in the parent and child process respectively. The prepare handlers are called in reverse order of their registration, while parent and child handlers are called in the order in which they were registered. Any of the handlers may be NULL. Important: only async-signal-safe functions are allowed on the child side of fork(). See sigaction(2) for details. RETURN VALUES
If successful, the pthread_atfork() function will return zero; otherwise an error number will be returned to indicate the error. ERRORS
pthread_atfork() will fail if: [ENOMEM] The system lacked the necessary resources to add another handler to the list. SEE ALSO
fork(2) STANDARDS
pthread_atfork() conforms to ISO/IEC 9945-1:1996 (``POSIX.1''). BSD
August 12, 2004 BSD
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