WSTOPPED
#define WIFSTOPPED(x) ((x).w_stopval == WSTOPPED)
#define WIFSIGNALED(x) ((x).w_stopval != WSTOPPED && (x).w_termsig != 0)
#define WIFEXITED(x) ((x).w_stopval != WSTOPPED && (x).w_termsig == 0)
WEXITED | WTRAPPED | WSTOPPED | WCONTINUED | WNOWAIT) != 0)
options |= (WNOHANG|WUNTRACED|WEXITED|WSTOPPED|WTRAPPED|WCONTINUED);
# define WIFEXITED(s) (((union wait*)&(s))->w_stopval != WSTOPPED && \
~(WEXITED|WTRAPPED|WSTOPPED|WCONTINUED|WNOHANG|WNOWAIT))
if (arg & WSTOPPED)
#define WOPTMASK (WEXITED|WTRAPPED|WSTOPPED|WCONTINUED|WNOHANG|WNOWAIT)
if (!(options & WSTOPPED))
#define WOPTMASK (WEXITED|WTRAPPED|WSTOPPED|WCONTINUED|WNOHANG|WNOWAIT)