objective-c - 从 nstask 获取数据 - 与命令行通信 - 目标 c

Question

我知道如何向任务发送数据：

NSData *charlieSendData = [[charlieImputText stringValue] dataUsingEncoding:NSUTF8StringEncoding];
[[[task standardInput] fileHandleForWriting] writeData:charlieSendData];

但是我如何获得任务的响应？

以利亚

Answer 1

给出一个NSPipe或一个NSFileHandle作为任务的standardOutput，并从中读取。

NSTask * list = [[NSTask alloc] init];
[list setLaunchPath:@"/bin/ls"];
[list setCurrentDirectoryPath:@"/"];

NSPipe * out = [NSPipe pipe];
[list setStandardOutput:out];

[list launch];
[list waitUntilExit];
[list release];

NSFileHandle * read = [out fileHandleForReading];
NSData * dataRead = [read readDataToEndOfFile];
NSString * stringRead = [[[NSString alloc] initWithData:dataRead encoding:NSUTF8StringEncoding] autorelease];
NSLog(@"output: %@", stringRead);

请注意，如果您使用管道，则必须担心管道会被填满。如果你提供一个NSFileHandle替代，任务可以输出它想要的所有内容，而不必担心丢失任何内容，但你也会获得必须将数据写入磁盘的开销。

Answer 2

Swift 3 解决方案，您可以实现一个接受一个闭包FileHandle

let process = Process()
process.launchPath = launchPath
process.arguments = arguments

let stdOut = Pipe()
process.standardOutput = stdOut
let stdErr = Pipe()
process.standardError = stdErr

let handler =  { (file: FileHandle!) -> Void in
  let data = file.availableData
  guard let output = NSString(data: data, encoding: String.Encoding.utf8.rawValue)
    else { return}

  print(output.components(separatedBy: "\n").first!)
}

stdErr.fileHandleForReading.readabilityHandler = handler
stdOut.fileHandleForReading.readabilityHandler = handler

process.terminationHandler = { (task: Process?) -> () in
  stdErr.fileHandleForReading.readabilityHandler = nil
  stdOut.fileHandleForReading.readabilityHandler = nil
}

process.launch()
process.waitUntilExit()