ref: 3eb88c0d7a390c249fd74f973b6e6f14549b6a39
dir: /include/bits/darwin/amd64/arch/sigaction.h/
typedef unsigned int sigset_t;
typedef struct siginfo siginfo_t;
struct sigaction {
union {
void (*__sa_handler)(int);
void (*__sa_sigaction)(int, siginfo_t *, void *);
} __sigaction_u;
sigset_t sa_mask;
int sa_flags;
};
#define sa_handler __sigaction_u.__sa_handler
#define sa_sigaction __sigaction_u.__sa_sigaction