text: #include "usys.h"
  #include "ulib.h"
  
  int main(int argc, char **argv) {
    if(argc != 2) {
      puts("mkdir [dirname]");
      exit(1);
    }
  
    if(mkdir(argv[1]) < 0) {
      puts("mkdir: failed");
      exit(1);
    }
  
    exit(0);
  }
  