ref: a7ac020664f1de870b09807086565030246ad6fb
dir: /sys/src/libregexp/regerror.c/
#include <u.h> #include <libc.h> #include <regexp.h> void regerror(char *s) { char buf[132]; strcpy(buf, "regerror: "); strcat(buf, s); strcat(buf, "\n"); write(2, buf, strlen(buf)); exits("regerr"); }