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Top Forums Programming Need help with fork, forking multiple childs and shared memory Post 302341990 by helpmeforlinux on Friday 7th of August 2009 05:57:20 AM
Old 08-07-2009
Computer

#matrixmadhan

Sorry for late reply.

Actually i was implementing the above program so i was bit busy, still i m facing one problem as i said earlier, how do i know which child sent me a signal, its not SIGCHLD , i m sending user defined signal to parent, and in sig handler i m not able to know which child sent me a signal, my child is running forever, means once the particular child sent me a singnal i wiil reasign some task to it, but i m not able to identify.
 

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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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