ref: d2278660a0bce54ae4a5d37f2fbc6dd4c2f459c8
dir: /src/libc/stdlib/atexit.c/
#include <stdlib.h> #include <errno.h> #undef atexit extern void (*_exitf[_ATEXIT_MAX])(void); extern unsigned _exitn; int atexit(void (*fun)(void)) { if (_exitn == _ATEXIT_MAX) { errno = ENOMEM; return -1; } _exitf[_exitn++] = fun; return 0; }