Reading the contents of a file using POSIX functions

- (NSData*)readDataFromFileAtURL:(NSURL*)anURL {
    NSString* filePath = [anURL path];
    fd = open([filePath UTF8String], O_RDONLY);
    if (fd == -1)
return nil;
    NSMutableData* theData = [[[NSMutableData alloc] initWithLength:1024]
autorelease];
    if (theData) {
        void* buffer = [theData mutableBytes];
        NSUInteger bufferSize = [theData length];
        NSUInteger actualBytes = read(fd, buffer, bufferSize);
        if (actualBytes < 1024)
            [theData setLength:actualBytes];
}
close(fd);
    return theData;
}