1 files changed, 104 insertions, 0 deletions
diff --git a/getopt.c b/getopt.c
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+/*
+ * *    @(#)getopt.c    2.3 (smail) 5/30/87 
+ */
+
+/*
+ * 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 behavior of this getopt. However, I am not about to
+ * post a copy of anything licensed by AT&T. 
+ */
+
+#ifdef BSD
+ #include <strings.h>
+#else
+ #define index strchr
+ #include <string.h>
+#endif
+
+/* LINTLIBRARY */
+#ifndef NULL
+#define NULL    0
+#endif
+
+#define EOF    (-1)
+#define ERR(s, c)    if(opterr){\
+    extern int write(int, void *, unsigned);\
+    char errbuf[2];\
+    errbuf[0] = (char)c; errbuf[1] = '\n';\
+    (void) write(2, strlwr(argv[0]), (unsigned)strlen(argv[0]));\
+    (void) write(2, s, (unsigned)strlen(s));\
+    (void) write(2, errbuf, 2);}
+
+extern char    *index();
+
+int             opterr = 1;
+int             optind = 1;
+int             optopt;
+char           *optarg;
+
+int getopt(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][1] == '\0')
+                        return (EOF);
+            else if (strcmp(argv[optind], "--") == 0)
+            {
+                  optind++;
+                  return (EOF);
+            }
+      }
+      optopt = c = argv[optind][sp];
+      if (c == ':' || (cp = index(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);
+}