Finding out if a shell script ran to completion using ObjC

gistfile1.txt

NSBundle* myBundle = [NSBundle mainBundle];
NSString* myScript = [myBundle pathForResource:@"isScriptRunning"
                                            ofType:@"sh"
                                       inDirectory:@"ScriptsDir"];
    
    NSTask *task;
    task = [[NSTask alloc] init];
#if !__has_feature(objc_arc)
    [task autorelease];
#endif
    
    [task setLaunchPath: @"/bin/sh"];
    
    NSArray *arguments;
    arguments = @[
                  myScript,
                  ];
    [task setArguments: arguments];
    
    [task setStandardOutput: [NSPipe pipe]];
    [task setStandardInput:[NSPipe pipe]];
    
    NSFileHandle *file;
    file = [pipe fileHandleForReading];
    
    [task launch];
    
    NSData *data;
    data = [file readDataToEndOfFile];
    
    NSString *output;
    output = [[NSString alloc] initWithData: data encoding: NSUTF8StringEncoding];
    Debug ("script returned:\n%s", string.UTF8String);
    
    BOOL installerRunning = output.length > 0;
    
    return installerRunning;