The ANSI standard includes some system functions for raising and responding to signals, non-local jumping, and so on.
void abort(void); int atexit(void(* func) (void)); void exit(int status); char* getenv(const char* name); int system(const char* cmd); int setjmp(jmp_buf env); void longjmp(jmp_buf env, int val); _sig_func signal(int sig, _sig_func handler); int raise(int sig);
To process variable length argument lists, the ANSI library provides the following functions, implemented as macros:
void va_start(va_list args, param);
type va_arg(va_list args, type);
void va_end(va_list args);