getopt
為什么80%的碼農都做不了架構師?>>> ??
--------http://chinesefys.blog.51cto.com/3072467/843352
http://blog.chinaunix.net/uid-26357860-id-1886887.html
#include <stdio.h> #include <string.h> /** Here's something you've all been waiting for: the AT&T public domain* source for getopt(3). It is the code which was given out at the 1985* UNIFORUM conference in Dallas. I obtained it by electronic mail* directly from AT&T. The people there assure me that it is indeed* in the public domain.** There is no manual page. That is because the one they gave out at* UNIFORUM was slightly different from the current System V Release 2* manual page. The difference apparently involved a note about the* famous rules 5 and 6, recommending using white space between an option* and its first argument, and not grouping options that have arguments.* Getopt itself is currently lenient about both of these things. White* space is allowed, but not mandatory, and the last option in a group can* have an argument. That particular version of the man page evidently* has no official existence, and my source at AT&T did not send a copy.* The current SVR2 man page reflects the actual behavor of this getopt.* However, I am not about to post a copy of anything licensed by AT&T.*/#define ERR(s, c) if (opterr) printf("%s: %s%cn", argv[0], s, c)int opterr = 1; int optind = 1; int optopt = 0; char *optarg = 0;int xgetopt(int argc, char **argv, char *opts) {static int sp = 1;register int c;register char *cp;if(sp == 1)if(optind >= argc ||argv[optind][0] != '-' && 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)) == 0) {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('?');} elseoptarg = argv[optind++];sp = 1;} else {if(argv[optind][++sp] == '\0') {sp = 1;optind++;}optarg = NULL;}return(c); }
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轉載于:https://my.oschina.net/plp626/blog/186400
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