试图在Cocoa App中发送curl POST命令

我正在尝试使用cURL从Cocoa应用程序向我的Yamaha接收器发送POST请求.我正在使用NSTask来实现这一点,并相信我的语法正确:

NSTask *task;
task = [[NSTask alloc] init];
[task setLaunchPath: @"/usr/bin/"];

NSArray *arguments;
arguments = [NSArray arrayWithObjects: @"-c", @"curl -v -X POST -H \"Content-type:text/xml\" --data 'xml=On' http://172.19.24.23/YamahaRemoteControl/ctrl", nil];
[task setArguments: arguments];

[task launch];

我把它分配到我的应用程序中的一个按钮,它成功编译但是当我按下按钮时我会在日志中得到它.

 2013-12-06 11:06:27.907 MyApp[18361:303] user clicked powerOnReceiver button
2013-12-06 11:06:27.909 MyApp[18361:303] Couldn't posix_spawn: error 13
2013-12-06 11:06:27.911 MyApp[18361:303] (
    0   CoreFoundation                      0x00007fff897c641c __exceptionPreprocess + 172
    1   libobjc.A.dylib                     0x00007fff88e96e75 objc_exception_throw + 43
    2   CoreFoundation                      0x00007fff897c62cc +[NSException raise:format:] + 204
    3   Foundation                          0x00007fff87e71214 -[NSConcreteTask launchWithDictionary:] + 3167
    4   MyApp                               0x0000000100001c9a -[Receiver powerOnReceiver] + 218
    5   MyApp                               0x0000000100007053 -[AppDelegate powerOnReceiver:] + 67
    6   AppKit                              0x00007fff863733d0 -[NSApplication sendAction:to:from:] + 327
    7   AppKit                              0x00007fff8637324e -[NSControl sendAction:to:] + 86
    8   AppKit                              0x00007fff863bfd7d -[NSCell _sendActionFrom:] + 128
    9   AppKit                              0x00007fff863d9715 -[NSCell trackMouse:inRect:ofView:untilMouseUp:] + 2316
    10  AppKit                              0x00007fff863d8ae7 -[NSButtonCell trackMouse:inRect:ofView:untilMouseUp:] + 487
    11  AppKit                              0x00007fff863d81fd -[NSControl mouseDown:] + 706
    12  AppKit                              0x00007fff86359d08 -[NSWindow sendEvent:] + 11296
    13  AppKit                              0x00007fff862f8744 -[NSApplication sendEvent:] + 2021
    14  AppKit                              0x00007fff86148a29 -[NSApplication run] + 646
    15  AppKit                              0x00007fff86133803 NSApplicationMain + 940
    16  MyApp                               0x00000001000063e2 main + 34
    17  libdyld.dylib                       0x00007fff85ed05fd start + 1
)

我认为我的路径在这里是正确的,因此我不确定何时收到"无法posix_spawn:错误13"消息.任何想法将不胜感激.