CGPDFDocumentRelease

CGPDFDocumentRelease is a function in the Core Graphics framework of Apple's operating systems. Its primary purpose is to release a reference to a Core Graphics PDF document object. When a PDF document is loaded or created using functions like CGPDFDocumentCreateWithURL or CGPDFDocumentCreateWithData, a reference count is incremented for that document object. This reference counting mechanism helps manage the memory associated with the PDF document, ensuring that it is deallocated only when it is no longer in use.

Calling CGPDFDocumentRelease decrements the reference count of the provided CGPDFDocumentRef. If the reference count drops to zero, the underlying memory resources occupied by the PDF document are freed. This is a crucial step in preventing memory leaks. Developers are responsible for calling CGPDFDocumentRelease for every CGPDFDocumentRef obtained through creation functions or by retaining existing references using CGPDFDocumentRetain. Failure to do so can lead to memory being held onto unnecessarily, impacting application performance and stability. The function takes a single argument, a CGPDFDocumentRef representing the PDF document to be released.