NSTask only returning standardError in release build

问题

First of all, when debugging and running in Xcode everything works as expected.

But when I try to "share" my app, i.e. make a release build, my NSTask won't output any standardOutput while standardErrors ARE put out. How is that possible?

My code

- (id)initWithWindow:(NSWindow *)window {
    self = [super initWithWindow:window];
    if (self) {
        // Initialization code here.
    }
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(readPipe:) name:NSFileHandleReadCompletionNotification object:nil];
    return self;
}


-(void) watchFile:(NSNotification *)notification {
        NSString *path = [[notification userInfo] valueForKey:@"path"];

        task = [[NSTask alloc] init];
        [task setLaunchPath:@"/usr/bin/compass"];
        [task setCurrentDirectoryPath:path];

        NSArray *arguments;
        arguments = [NSArray arrayWithObjects: @"watch",@"--boring", nil];
        [task setArguments: arguments];

        NSPipe *outPipe, *errPipe;
        outPipe = [NSPipe pipe];
        errPipe = [NSPipe pipe];
        [task setStandardOutput: outPipe];
        [task setStandardError: errPipe];
        [task setStandardInput: [NSPipe pipe]];

        standardHandle = [outPipe fileHandleForReading];
        [standardHandle readInBackgroundAndNotify];

        errorHandle = [errPipe fileHandleForReading];
        [errorHandle readInBackgroundAndNotify];

        [self setSplitterPosition:0.0f];

        [task launch];

    }

-(void)readPipe:(NSNotification *)notification {
        NSLog(@"reading pipe");
        NSData *data;
        NSString *text;

        if(!([notification object] == standardHandle) && !([notification object] == errorHandle)) {
            return;
        } 

        data = [[notification userInfo] objectForKey:NSFileHandleNotificationDataItem];
        text = [[NSString alloc] initWithData:data encoding:NSASCIIStringEncoding];

        if ([data length] == 0) {
            //error
            [self setSplitterPosition:150.0f];
            return;
        }

        [terminalViewController updateTerminal:text];    
        if(![text isEqualToString:@"\n"]) [self growlAlert:text title:@"Compapp"];

        [text release];
        if(task) [[notification object] readInBackgroundAndNotify];
    }

回答1:

/usr/bin/compass is not a binary installed in the standard installation of OSX (I don't have any binary named compass in my /usr/bin on my Mac)

So it seems quite logical that when your app is running on another Mac -- that does not have /usr/bin/compass installed -- and you try to run this task, it can't find it and only output some error on stderr.

回答2:

If you mean after release you are trying to debug, you need to create a file called Entitlements.plist and set Can be debugged before you build and archive.

回答3:

if this is still an open issue for you, then checkout the answer I posted at this link: How to use a determinate NSProgressIndicator to check on the progress of NSTask? - Cocoa

it provides a good template for creating an async NSTask and for reading from standard output or standard error.

来源：https://stackoverflow.com/questions/8254680/nstask-only-returning-standarderror-in-release-build

标签

objective-c

macos

cocoa

nstask

nsfilehandle