1 files changed, 77 insertions, 0 deletions
diff --git a/7.7/main.c b/7.7/main.c
new file mode 100644
index 0000000..ee944b4
--- /dev/null
+++ b/7.7/main.c
@@ -0,0 +1,77 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stdbool.h>
+
+#define MAXLINE 1000
+
+struct flags {
+	unsigned int except : 1;
+	unsigned int number : 1;
+} flags;
+
+void fpat(FILE *fp, char *fname, char *pattern, struct flags flags);
+
+int main(int argc, char *argv[])
+{
+	FILE *fp;
+	char pattern[MAXLINE];
+
+	while (--argc > 0 && **++argv == '-') {
+		while (*++*argv) {
+			switch (**argv) {
+			case 'x':
+				flags.except = true;
+				break;
+			case 'n':
+				flags.number = true;
+				break;
+			default:
+				fprintf(stderr, "find: %c: unknown flag\n", **argv);
+				exit(1);
+				break;
+			}
+		}
+	}
+
+	if (argc >= 1) {
+	 	strncpy(pattern, *argv, MAXLINE);
+	} else {
+		fprintf(stderr, "Usage: find -xn pattern [file ...]\n");
+		exit(1);
+	}
+
+	if (argc == 1) {
+		fpat(stdin, "", pattern, flags);
+		fp = stdin;
+	} else {
+		while (--argc > 0) {
+			if (!(fp = fopen(*++argv, "r"))) {
+				fprintf(stderr, "find: can't open %s\n", *argv);
+				exit (1);
+			} else {
+				fpat(fp, *argv, pattern, flags);
+				fclose(fp);
+			}
+		}
+	}
+
+	return 0;
+}
+
+void fpat(FILE *fp, char *fname, char *pattern, struct flags flags)
+{
+	char line[MAXLINE];
+	unsigned long lineno;
+
+	lineno = 0;
+	while (fgets(line, MAXLINE, fp) != NULL) {
+		if (!!(strstr(line, pattern)) != flags.except) {
+			if (*fname)
+				printf("%s - ", fname);
+			if (flags.number)
+				printf("%5lu: ", ++lineno);
+			printf("%s", line);
+		}
+	}
+}