ref: a7c01127f9749fe471367c6461cde357403cc3b3
dir: /sys/src/ape/lib/bsd/getopt.c/
#include <stdlib.h> #include <string.h> #include <stdio.h> #define ERR(str, chr) if(opterr){fprintf(stderr, "%s%s%c\n", argv[0], str, chr);} int opterr = 1; int optind = 1; int optopt; char *optarg; int getopt (int argc, char **argv, char *opts) { static int sp = 1; register c; register char *cp; if (sp == 1) if (optind >= argc || argv[optind][0] != '-' || argv[optind][1] == '\0') return EOF; else if (strcmp(argv[optind], "--") == 0) { optind++; return EOF; } optopt = c = argv[optind][sp]; if (c == ':' || (cp=strchr(opts, c)) == NULL) { ERR (": illegal option -- ", c); if (argv[optind][++sp] == '\0') { optind++; sp = 1; } return '?'; } if (*++cp == ':') { if (argv[optind][sp+1] != '\0') optarg = &argv[optind++][sp+1]; else if (++optind >= argc) { ERR (": option requires an argument -- ", c); sp = 1; return '?'; } else optarg = argv[optind++]; sp = 1; } else { if (argv[optind][++sp] == '\0') { sp = 1; optind++; } optarg = NULL; } return c; }