more cleaning

cut/cut.c

@@ -0,0 +1,67 @@
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <sysexits.h>
+#include <unistd.h>
+#include "noargvzero.h"
+
+extern char *optarg; /* getopt(3); unistd.h */
+extern int optind, opterr, optopt; /* getopt(3); unistd.h */
+
+void
+occurrences(FILE *f, char *s){
+
+}
+
+void
+usage(char *name){
+	fprintf(stderr,
+		"Usage: %s (-b [list] (-n))"
+			"\t|(-c [list])"
+			"\t|(-f [list] (-d [delim]) (-s))"
+			"\t[file...]\n", name);
+	exit(EX_USAGE);
+}
+
+int
+main(int argc, char *argv[]){
+	int c;
+	char *delimiter;
+	char *list;
+	char mode;
+
+	NOARGVZERO(argv[0]);
+
+	/* perhaps mode could be specified after submodal stuff. this would
+	 * move checks to after argument parsing though which could take more
+	 * time. */
+	mode = 0;
+	submode = 0;
+	while((c = getopt(argc, argv, "b:c:d:f:ns")) != -1)
+		switch(c){
+			case 'b': case 'c': case 'f':
+				if(mode != 0)
+					usage(argv[0]);
+				mode = c;
+				list = optarg;
+				break;
+
+			case 'd':
+				if(mode != 'f')
+					usage(argv[0]);
+				delimiter = optarg;
+				break;
+
+			case 'n': case 's':
+				if((c == 's' && mode != 'f')
+						|| (c == 'b' && mode != 'b'))
+					usage(argv[0]);
+				submode = c;
+				break;
+
+			default:
+				usage(argv[0]);
+		}
+
+	return EX_OK;
+}