getopt

getopt/Makefile

@@ -0,0 +1,15 @@
+CC = gcc
+CFLAGS = -Wall -O2
+
+all: getopt.elf getopt_long.elf
+
+getopt.elf: getopt.c
+	@echo CC $@
+	@$(CC) $(CFLAGS) -o $@ $^ $(LDFLAGS)
+
+getopt_long.elf: getopt_long.c
+	@echo CC $@
+	@$(CC) $(CFLAGS) -o $@ $^ $(LDFLAGS)
+
+clean:
+	rm -f *.elf

getopt/getopt.c

@@ -0,0 +1,15 @@
+#include <stdio.h>
+#include <unistd.h>
+
+int main(int argc, char *argv[]) {
+    int opt;
+    while ((opt = getopt(argc, argv, "hf:o:")) != -1) {
+        switch (opt) {
+        case 'h': puts("Help"); break;
+        case 'f': printf("File: %s\n", optarg); break;
+        case 'o': printf("Output: %s\n", optarg); break;
+        default: fprintf(stderr, "Usage: %s [-h] [-f file] [-o output]\n", argv[0]); return 1;
+        }
+    }
+    return 0;
+}

getopt/getopt_long.c

@@ -0,0 +1,38 @@
+#include <getopt.h>
+#include <stdio.h>
+#include <string.h>
+
+#define VERSION "0.0.1"
+
+int main(int argc, char *argv[]) {
+    int                  opt;
+    int                  option_index = 0;
+    static struct option long_opts[] = {
+        {"help", no_argument, 0, 'h'},
+        {"file", required_argument, 0, 'f'},
+        {"output", required_argument, 0, 'o'},
+        {"version", no_argument, 0, 'v'},
+        {0, 0, 0, 0},
+    };
+
+    int  has_file = 0;
+    char a[128];
+
+    while ((opt = getopt_long(argc, argv, "hvf:o:", long_opts, &option_index)) != -1) {
+        switch (opt) {
+        case 'h': puts("Help"); break;
+        case 'f':
+            printf("File: %s\n", optarg);
+            strncpy(a, optarg, 127);
+            has_file = 1;
+            break;
+        case 'o': printf("Output: %s\n", optarg); break;
+        case 'v': printf("Version: v%s\n", VERSION); break;
+        default: return 1;
+        }
+    }
+
+    if (has_file)
+        printf("Using file: %s\n", a);
+    return 0;
+}