Swift，在GCD中，SIGUSR1不起作用

Question

以下尝试形成代码，但SIGUSR1的触发器不起作用。 什么是不够的？

signal(SIGUSR1, SIG_IGN);
let que = dispatch_queue_create("Que", DISPATCH_QUEUE_CONCURRENT)
let source = dispatch_source_create(DISPATCH_SOURCE_TYPE_SIGNAL, UInt(SIGUSR1), 0, que)

dispatch_source_set_event_handler(source, {
    NSLog("BLOCK doing")
})

dispatch_resume(source)

sigaction(SIGUSR1, nil, nil)

Answer 1

研究资源＆＃34; Swift中的信号处理＆＃34;：

1. Kernel Architecture Overview
2. iOS Developer Library: signal
3. iOS Developer Library: sigaction
4. Github IBM-Swift/BlueSignals/.../Sources/Signals.swift

代码（创建命令行工具项目）

import Foundation

var signalSource: dispatch_source_t!
var signalOnceToken = dispatch_once_t()
let signalID:Int32 = SIGUSR1

func initSignalHandler(signal: Int32) {
    dispatch_once(&signalOnceToken) {

    let queue = dispatch_queue_create("queue", DISPATCH_QUEUE_CONCURRENT)
        signalSource = dispatch_source_create(DISPATCH_SOURCE_TYPE_SIGNAL,
                                               UInt(signal), 0, queue)
        if let source = signalSource {
            dispatch_source_set_event_handler(source) {
                NSLog("signal: \(signal)")
            }
            dispatch_resume(source)
        }
    }
}

initSignalHandler(signalID)

sleep(1)

// send signal
Darwin.raise(signalID)

NSLog("End")

结果图像