我正在 sbcl 中编写一个程序,使用加法和移位法将两个数字相乘。虽然我的普通程序可以很好地运行,但是当我使用线程时,程序没有输出也没有错误消息。代码中是否有我应该删除的错误。
(use-package :sb-thread)
(defvar *buffer-queue* (make-waitqueue))
(defvar *buffer-lock* (make-mutex :name "buffer-lock"))
(defvar *buffer* (list nil))
(defun writer()
(let ((res 0))
(loop for lpr from 0 to 63
do (let ((end-bit (logand num2 1)))
(with-mutex (*buffer-lock*)
(setf *buffer* (cons end-bit *buffer*))
(setq num2 (ash num2 -1))
(condition-notify *buffer-queue*)
)))))
(defun reader()
(let ((end-bit 0) (res 0))
(with-mutex (*buffer-lock*)
(loop
(condition-wait *buffer-queue* *buffer-lock*)
(loop
(unless *buffer* (return))
(end-bit (car *buffer*))
(setf *buffer* (cdr *buffer*)))))
(if (= end-bit 1)
(setq res (+ res num1)))
(setq num1 (ash num1 1))
(format t "result is ~a.~%" res)
)
)
(let ((num1 (progn
(write-line "Enter first number: ")
(finish-output)
(read)))
(num2 (progn
(write-line "Enter second number: ")
(finish-output)
(read))))
(if (or (= num1 0) (= num2 0))
(write-line "result is 0.0")
(calculator num1 num2))
)
为什么会这样?
最佳答案
为了弄清楚发生了什么,我强烈建议使用 (trace writer)
和 (trace reader)
(甚至可能是 (trace calculator)
).
我还建议使用 bordeaux-thread,它只是一个 shim(法语中的 bordeaux = shim),使线程可以在多个实现上工作。
关于multithreading - 在 sbcl lisp 中使用线程时,变量在 lisp 中未绑定(bind),我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/27764517/