text: #include "types.h"
  #include "stat.h"
  #include "user.h"
  #include "pstat.h"
  
  #define check(exp, msg) if(exp) {} else {\
     printf(1, "%s:%d check (" #exp ") failed: %s\n", __FILE__, __LINE__, msg);\
     exit();}
  
  int
  main(int argc, char *argv[])
  {
     check(settickets(1) == 0, "settickets to 1");
     check(settickets(1000000) == 0, "settickets to 1000000");
     check(settickets(0) == -1, "settickets to 0");
     check(settickets(-1) == -1, "settickets to < 0");
     printf(1, "Should print 1 then 2");
     exit();
  }
  