send HTTP PATCH request in iOS (Objective-c)
<p>I am consuming REST APIs, one of the api is <code>PATCH</code>, i tried to invoke it using following code but it throws error, while same api works in <code>Postman</code> client.</p>

<pre><code>+ (NSURLSessionTask *)callPATCHAPIWithAPIName:(NSString *)apiName andCompletionHandler:(void(^)(id result, NSInteger responseCode, NSError *error))completionHandler
{
    NSString *getURL = @"192.168.1.100/UpdateDeviceInfo/iPhone6/OS 9.2";
    NSURL *URL = [NSURL URLWithString:getURL];
    NSMutableURLRequest *request = [[NSMutableURLRequest alloc] initWithURL:URL];

    NSURLSessionConfiguration *sessionConfiguration = [NSURLSessionConfiguration defaultSessionConfiguration];
    sessionConfiguration.timeoutIntervalForRequest = 45.0f;

    NSURLSession *session = [NSURLSession sessionWithConfiguration:sessionConfiguration];

    // Create Data from request
    NSData *requestData = [NSData dataWithBytes: [@"" UTF8String] length:[@"" length]];

    [request setHTTPMethod:@"PATCH"];
    [request setValue:[NSString stringWithFormat:@"%lu", (unsigned long)[requestData length]] forHTTPHeaderField:@"Content-Length"];

    [request setHTTPBody:requestData];

    NSURLSessionDataTask *task = [session dataTaskWithRequest:request
                                            completionHandler:
                                  ^(NSData *data, NSURLResponse *response, NSError *error)
                                  {
                                      NSHTTPURLResponse *httpResponse = (NSHTTPURLResponse *) response;

                                      NSInteger responseCode = [httpResponse statusCode];
                                      NSLog(@"response Code : %ld",(long)responseCode);
                                  }];

    [task resume];
    return task;
}
</code></pre>

<blockquote>
  <p>[Error :Error Domain=NSURLErrorDomain Code=-1002 "unsupported URL" UserInfo={NSLocalizedDescription=unsupported URL, NSUnderlyingError=0x14e86d490 {Error Domain=kCFErrorDomainCFNetwork Code=-1002 "(null)"}}]</p>
</blockquote>

<p>I am passing parameters in query string, not in request body. Though same thing is working in <code>Postman</code> client &amp; Android.</p>