ref: 90baca8302fd8b6ccad7d06b61da9ecf451ccf83
dir: /libc/atexit.c/
#include <u.h> #include <libc.h> #define NEXIT 33 typedef struct Onex Onex; struct Onex{ void (*f)(void); int pid; }; static Lock onexlock; Onex onex[NEXIT]; int atexit(void (*f)(void)) { int i; lock(&onexlock); for(i=0; i<NEXIT; i++) if(onex[i].f == 0) { onex[i].pid = getpid(); onex[i].f = f; unlock(&onexlock); return 1; } unlock(&onexlock); return 0; } void exits(char *s) { int i, pid; void (*f)(void); pid = getpid(); for(i = NEXIT-1; i >= 0; i--) if((f = onex[i].f) && pid == onex[i].pid) { onex[i].f = 0; (*f)(); } exit(s && *s); }