在AWE4.0中替代awful.util.pread

Question

在AWE3.5中，我曾经使用依赖于awful.util.pread()的自定义小部件。在AWE4.0中，我被指示使用awful.spawn.easy_async()代替

我试着替换这个：

local cmd = "echo 5555"
local ret = "5"
ret = awful.util.pread(cmd)

-- ret contains 5555

有了这个：

local cmd = {"bash", "-c", "echo 5555"}
local ret = "5"
awful.spawn.easy_async(cmd, function(stdout, stderr, reason, exit_code)
    ret = stdout
end)

-- ret contains 5

变量ret保持不变。如何使用awful.spawn函数重现awful.util.pread()的行为？

Answer 1

easy_async是异步的，所以你应该在回调中调用函数，赋值将不会持久：

local cmd = {"bash", "-c", "echo 5555"}
awful.spawn.easy_async(cmd, function(stdout, stderr, reason, exit_code)
  naughty.notify { text = "output is " .. stdout }
end)
-- the anonymous function has not been called yet when this comment is reached