Fixed syntax error, and bug at https://developer.apple.com/library/mac/#documentation/graphicsimaging/Conceptual/drawingwithquartz2d/dq_pdf/dq_pdf.html#//apple_ref/doc/uid/TP30001066-CH214-BCIBGJFC

MyCreatePDFFile.m

void MyCreatePDFFile (CGRect pageRect, const char *filename)// 1
{
  CGContextRef pdfContext;
  CFStringRef path;
  CFURLRef url;
  CFDataRef boxData = NULL;
  CFMutableDictionaryRef myDictionary = NULL;
  CFMutableDictionaryRef pageDictionary = NULL;
  
  path = CFStringCreateWithCString (NULL, filename, // 2
                                    kCFStringEncodingUTF8);
  url = CFURLCreateWithFileSystemPath (NULL, path, // 3
                                       kCFURLPOSIXPathStyle, 0);
  CFRelease (path);
  myDictionary = CFDictionaryCreateMutable(NULL, 0,
                                           &kCFTypeDictionaryKeyCallBacks,
                                           &kCFTypeDictionaryValueCallBacks); // 4
  CFDictionarySetValue(myDictionary, kCGPDFContextTitle, CFSTR("My PDF File"));
  CFDictionarySetValue(myDictionary, kCGPDFContextCreator, CFSTR("My Name"));
  pdfContext = CGPDFContextCreateWithURL (url, &pageRect, myDictionary); // 5
  CFRelease(myDictionary);
  CFRelease(url);
  pageDictionary = CFDictionaryCreateMutable(NULL, 0,
                                             &kCFTypeDictionaryKeyCallBacks,
                                             &kCFTypeDictionaryValueCallBacks); // 6
  boxData = CFDataCreate(NULL,(const UInt8 *)&pageRect, sizeof (CGRect));
  CFDictionarySetValue(pageDictionary, kCGPDFContextMediaBox, boxData);
  CGPDFContextBeginPage (pdfContext, pageDictionary); // 7

// insert_draw_something (pdfContext);

  CGPDFContextEndPage (pdfContext);// 9
  CGContextRelease (pdfContext);// 10
  CFRelease(pageDictionary); // 11
  CFRelease(boxData);
}