ref: c35217a1a61f795d312eede2f84faf59c7c06a3c dir: /lib/c/strerror.c/
#include <errno.h> #include <string.h> #undef strerror char * strerror(int errnum) { if (errnum < _sys_nerr) return _sys_errlist[errnum]; else return "Unknown error"; }