ls: Use command-line arguments

apps/src/ls.c

@@ -1,22 +1,31 @@
 #include <dirent.h>
 #include <fcntl.h>
+#include <stdbool.h>
 #include <stdio.h>
 #include <unistd.h>
 
-int main()
+int main(int argc, char** argv)
 {
-    DIR* dp = opendir("/bin");
+    const char* pathname;
+    if (argc == 1) pathname = "/";
+    else
+        pathname = argv[1];
+    DIR* dp = opendir(pathname);
     if (!dp)
     {
         perror("opendir");
         return 1;
     }
+    bool first_ent = true;
     do {
         struct dirent* ent = readdir(dp);
         if (!ent) break;
-        printf("%s\n", ent->d_name);
+        printf(first_ent ? "%s" : " %s", ent->d_name);
+        first_ent = false;
     } while (1);
 
+    printf("\n");
+
     closedir(dp);
     return 0;
 }