#!/usr/sbin/dtrace -wqs /* * guess.d - guessing game in D (DTrace) * * $Id: guess.d,v 1.1.1.1 2015/09/30 22:01:07 christos Exp $ * * USAGE: guess.d * * SEE: http://www.brendangregg.com/guessinggame.html * * This is written to demonstrate this language versus the same program * written in other languages. * * 11-May-2005 Brendan Gregg Created this. */ inline string scorefile = "highscores_d"; dtrace:::BEGIN { printf("guess.d - Guess a number between 1 and 100\n\n"); num = 1; state = 1; /* Generate random number */ answer = (rand() % 100) + 1; answer = answer > 0 ? answer : - answer; } syscall::write:entry /state == 1 && pid == $pid/ { state = 2; printf("Enter guess %d: ", num); system("read guess"); pos = 0; } syscall::read:entry /state == 2 && ppid == $pid && arg0 == 3/ { self->inguess = 1; self->buf = arg1; } syscall::read:return /self->inguess/ { key = copyin(self->buf, arg0); keys[pos] = *(char *)key; self->buf = 0; pos++; } syscall::read:return /self->inguess && keys[pos-1] == '\n'/ { pos -= 2; fac = 1; guess = fac * (keys[pos] - '0'); pos--; fac *= 10; guess = pos >= 0 ? guess + fac * (keys[pos] - '0') : guess; pos--; fac *= 10; guess = pos >= 0 ? guess + fac * (keys[pos] - '0') : guess; self->doneguess = 1; } syscall::read:return /self->inguess/ { self->inguess = 0; } /* Play game */ syscall::read:return /self->doneguess && guess == answer/ { printf("Correct! That took %d guesses.\n\n", num); self->doneguess = 0; state = 3; printf("Please enter your name: "); system("/usr/bin/read name"); } syscall::read:return /self->doneguess && guess != answer/ { num++; printf("%s...\n", guess < answer ? "Higher" : "Lower"); printf("Enter guess %d: ", num); system("read line"); pos = 0; } syscall::read:entry /state == 3 && curthread->t_procp->p_parent->p_ppid == $pid && arg0 == 0/ { self->inname = 1; self->buf = arg1; } /* Save high score */ syscall::read:return /self->inname/ { self->inname = 0; name = stringof(copyin(self->buf, arg0 - 1)); system("echo %s %d >> %s", name, num, scorefile); /* Print high scores */ printf("\nPrevious high scores,\n"); system("cat %s", scorefile); exit(0); }