ref: c0fedecd530af29e777f1f17e0634336d8675c79
dir: /sys/src/libc/port/perror.c/
#include <u.h> #include <libc.h> void perror(char *s) { char buf[ERRMAX]; buf[0] = '\0'; errstr(buf, sizeof buf); if(s && *s) fprint(2, "%s: %s\n", s, buf); else fprint(2, "%s\n", buf); }