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

     pthread_atfork -- register handlers to be called before and after fork()

     #include <pthread.h>

     pthread_atfork(void (*prepare)(void), void (*parent)(void), void (*child)(void));

     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.

     If successful, the pthread_atfork() function will return zero; otherwise an error number will be
     returned to indicate the error.

     pthread_atfork() will fail if:

     [ENOMEM]           The system lacked the necessary resources to add another handler to the list.


     pthread_atfork() conforms to ISO/IEC 9945-1:1996 (``POSIX.1'').

BSD                             August 12, 2004                            BSD

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