iOS AudioStreamBasicDescription NSLog 输出

#pragma mark -
#pragma mark Utility methods

// You can use this method during development and debugging to look at the
//    fields of an AudioStreamBasicDescription struct.
- (void) printASBD: (AudioStreamBasicDescription) asbd {

    char formatIDString[5];
    UInt32 formatID = CFSwapInt32HostToBig (asbd.mFormatID);
    bcopy (&formatID, formatIDString, 4);
    formatIDString[4] = '\0';
    
    NSLog (@"  Sample Rate:         %10.0f",  asbd.mSampleRate);
    NSLog (@"  Format ID:           %10s",    formatIDString);
    NSLog (@"  Format Flags:        %10X",    (unsigned int)asbd.mFormatFlags);
    NSLog (@"  Bytes per Packet:    %10d",    (unsigned int)asbd.mBytesPerPacket);
    NSLog (@"  Frames per Packet:   %10d",    (unsigned int)asbd.mFramesPerPacket);
    NSLog (@"  Bytes per Frame:     %10d",    (unsigned int)asbd.mBytesPerFrame);
    NSLog (@"  Channels per Frame:  %10d",    (unsigned int)asbd.mChannelsPerFrame);
    NSLog (@"  Bits per Channel:    %10d",    (unsigned int)asbd.mBitsPerChannel);
}


- (void) printErrorMessage: (NSString *) errorString withStatus: (OSStatus) result {

    char resultString[5];
    UInt32 swappedResult = CFSwapInt32HostToBig (result);
    bcopy (&swappedResult, resultString, 4);
    resultString[4] = '\0';

//    NSLog (
//        @"*** %@ error: %s %08X %4.4s\n",
//                errorString,
//                (char*) &resultString
//    );
}