wait3, wait364 - wait for status change of child processes

Syntax	#include <sys/wait.h> pid_t wait3(int *stat_loc, int options, struct rusage *resource_usage);  CRTE111A30 pid_t wait364(int *stat_loc, int options, struct rusage64 *resource_usage);  (End)
Description	wait3() returns status information on the specified child process to the calling process. The call wait3(stat_loc, options, resource_usage); is equivalent to the call waitpid( (pid_t)-1, stat_loc, options); except that on successful execution in the specified rusage structure resource_usage, the status information for the child process identified by the return value is entered. wait3() is not thread-safe. If threads are used, the wait() and waitpid() functions affect the process or a thread in the following manner: wait3() returns status information on the specified child process to the calling thread. The function wait364() behaves like the function wait3(), except that the argument r_usage points to a structure rusage instead of a structure rusage. The structure rusage contains the following components: struct timeval ru_utime /* The total time the execution takes in user mode. The interval is specified in seconds and microseconds. */ struct timeval ru_stime /* The total time the execution takes in system mode. The interval is specified in seconds and microseconds. */ The structure rusage64 contains the following components: struct timeval64 ru_utime /* The total time the execution takes in user mode. The interval is specified in seconds and microseconds. */ struct timeval64 ru_stime /* The total time the execution takes in system mode. The interval is specified in seconds and microseconds. */
Return val.	see waitpid(). In addition to the errors specified for waitpid(), wait3() will fail if:
Errors	see waitpid(). In addition to the errors specified for waitpid(), wait3() and wait364() will fail if:
	ECHILD	For the calling process there are no child processes which are not waited for, or the group of processes specified by the pid argument can never acquire the status specified by options.
	In addition to the errors specified for waitpid(), wait364() will fail if:
	ENOSYS	POSIX-BC correction status < A47.
Notes	If a parent process is terminated without waiting for its child processes, the initialization process (process ID = 1) takes over the child processes.
See also	exec, exit(), fork(), pause(), sys/wait.h.