Close a PDF document

Releases the underlying PDFium handle. Idempotent — calling pdf_doc_close() on an already-closed document is a no-op. The finalizer registered at pdf_doc_open() also calls this when the R object is garbage-collected, but explicit close is recommended when handling many large documents or when a subsequent operation needs to delete the source file (relevant on Windows).

Usage

pdf_doc_close(doc)

Arguments

doc

A pdfium_doc produced by pdf_doc_open().

Value

Invisibly returns doc with its underlying pointer marked closed.

Details

Handles still open on the document are closed first, because PDFium expects them to be closed before their document: annotation handles, including the form-field handles of pdf_form_fields(), then pages, then fonts and XObjects. Afterwards they print as closed, and calls on them, or on page-objects read from the closed pages, raise an error. Close a document when you are done with everything read from it.