diff --git a/tools/zipalign/ZipAlignMain.cpp b/tools/zipalign/ZipAlignMain.cpp
index 47ebd12..53fc8d4 100644
--- a/tools/zipalign/ZipAlignMain.cpp
+++ b/tools/zipalign/ZipAlignMain.cpp
@@ -20,6 +20,7 @@
 
 #include "ZipAlign.h"
 
+#include <getopt.h>
 #include <stdio.h>
 #include <stdlib.h>
 
@@ -60,69 +61,53 @@
     int alignment;
     char* endp;
 
-    if (argc < 4) {
-        wantUsage = true;
-        goto bail;
-    }
-
-    argc--;
-    argv++;
-
-    while (argc && argv[0][0] == '-') {
-        const char* cp = argv[0] +1;
-
-        while (*cp != '\0') {
-            switch (*cp) {
-            case 'c':
-                check = true;
-                break;
-            case 'f':
-                force = true;
-                break;
-            case 'v':
-                verbose = true;
-                break;
-            case 'z':
-                zopfli = true;
-                break;
-            case 'p':
-                pageAlignSharedLibs = true;
-                break;
-            default:
-                fprintf(stderr, "ERROR: unknown flag -%c\n", *cp);
-                wantUsage = true;
-                goto bail;
-            }
-
-            cp++;
+    int opt;
+    while ((opt = getopt(argc, argv, "fcpvz")) != -1) {
+        switch (opt) {
+        case 'c':
+            check = true;
+            break;
+        case 'f':
+            force = true;
+            break;
+        case 'v':
+            verbose = true;
+            break;
+        case 'z':
+            zopfli = true;
+            break;
+        case 'p':
+            pageAlignSharedLibs = true;
+            break;
+        default:
+            fprintf(stderr, "ERROR: unknown flag -%c\n", opt);
+            wantUsage = true;
+            goto bail;
         }
-
-        argc--;
-        argv++;
     }
 
-    if (!((check && argc == 2) || (!check && argc == 3))) {
+    if (!((check && (argc - optind) == 2) || (!check && (argc - optind) == 3))) {
         wantUsage = true;
         goto bail;
     }
 
-    alignment = strtol(argv[0], &endp, 10);
+    alignment = strtol(argv[optind], &endp, 10);
     if (*endp != '\0' || alignment <= 0) {
-        fprintf(stderr, "Invalid value for alignment: %s\n", argv[0]);
+        fprintf(stderr, "Invalid value for alignment: %s\n", argv[optind]);
         wantUsage = true;
         goto bail;
     }
 
     if (check) {
         /* check existing archive for correct alignment */
-        result = verify(argv[1], alignment, verbose, pageAlignSharedLibs);
+        result = verify(argv[optind + 1], alignment, verbose, pageAlignSharedLibs);
     } else {
         /* create the new archive */
-        result = process(argv[1], argv[2], alignment, force, zopfli, pageAlignSharedLibs);
+        result = process(argv[optind + 1], argv[optind + 2], alignment, force, zopfli, pageAlignSharedLibs);
 
         /* trust, but verify */
         if (result == 0) {
-            result = verify(argv[2], alignment, verbose, pageAlignSharedLibs);
+            result = verify(argv[optind + 2], alignment, verbose, pageAlignSharedLibs);
         }
     }