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diff --git a/awklib/eg/lib/getopt.awk b/awklib/eg/lib/getopt.awk
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+# getopt --- do C library getopt(3) function in awk
+#
+# arnold@gnu.ai.mit.edu
+# Public domain
+#
+# Initial version: March, 1991
+# Revised: May, 1993
+
+# External variables:
+#    Optind -- index of ARGV for first non-option argument
+#    Optarg -- string value of argument to current option
+#    Opterr -- if non-zero, print our own diagnostic
+#    Optopt -- current option letter
+
+# Returns
+#    -1     at end of options
+#    ?      for unrecognized option
+#    <c>    a character representing the current option
+
+# Private Data
+#    _opti  index in multi-flag option, e.g., -abc
+function getopt(argc, argv, options,    optl, thisopt, i)
+{
+    optl = length(options)
+    if (optl == 0)        # no options given
+        return -1
+
+    if (argv[Optind] == "--") {  # all done
+        Optind++
+        _opti = 0
+        return -1
+    } else if (argv[Optind] !~ /^-[^: \t\n\f\r\v\b]/) {
+        _opti = 0
+        return -1
+    }
+    if (_opti == 0)
+        _opti = 2
+    thisopt = substr(argv[Optind], _opti, 1)
+    Optopt = thisopt
+    i = index(options, thisopt)
+    if (i == 0) {
+        if (Opterr)
+            printf("%c -- invalid option\n",
+                                  thisopt) > "/dev/stderr"
+        if (_opti >= length(argv[Optind])) {
+            Optind++
+            _opti = 0
+        } else
+            _opti++
+        return "?"
+    }
+    if (substr(options, i + 1, 1) == ":") {
+        # get option argument
+        if (length(substr(argv[Optind], _opti + 1)) > 0)
+            Optarg = substr(argv[Optind], _opti + 1)
+        else
+            Optarg = argv[++Optind]
+        _opti = 0
+    } else
+        Optarg = ""
+    if (_opti == 0 || _opti >= length(argv[Optind])) {
+        Optind++
+        _opti = 0
+    } else
+        _opti++
+    return thisopt
+}
+BEGIN {
+    Opterr = 1    # default is to diagnose
+    Optind = 1    # skip ARGV[0]
+
+    # test program
+    if (_getopt_test) {
+        while ((_go_c = getopt(ARGC, ARGV, "ab:cd")) != -1)
+            printf("c = <%c>, optarg = <%s>\n",
+                                       _go_c, Optarg)
+        printf("non-option arguments:\n")
+        for (; Optind < ARGC; Optind++)
+            printf("\tARGV[%d] = <%s>\n",
+                                    Optind, ARGV[Optind])
+    }
+}