Register fork handlers
#include <process.h> int pthread_atfork( void (*prepare)(void), void (*parent)(void), void (*child)(void) );
Use the -l c option to qcc to link against this library. This library is usually included automatically.
The pthread_atfork() function registers fork handler functions to be called before and after a fork(), in the context of the thread that called fork(). You can set one or more of the arguments to NULL to indicate no handler.
You can register multiple prepare, parent, and child fork handlers, by making additional calls to pthread_atfork(). In this case, the parent and child handlers are called in the order they were registered, and the prepare handlers are called in the reverse order.
You can't use the pthread_atfork() function for useful purposes as the C library doesn't have the necessary handlers. It also implies that Neutrino currently doesn't support fork() in multi-threaded programs.
POSIX 1003.1 THR
Processes and Threads chapter of Getting Started with QNX Neutrino