Read one entry from a PDF's Info dictionary

Wraps FPDF_GetMetaText. Returns the requested standard or custom Info-dictionary tag value as a UTF-8 string, or "" when the tag is absent. Standard tags are "Title", "Author", "Subject", "Keywords", "Creator", "Producer", "CreationDate", "ModDate", "Trapped". Custom tags from a particular producer's Info dictionary are also accepted.

Usage

pdf_doc_meta(doc, tag)

Arguments

doc

A pdfium_doc from pdf_doc_open().

tag

Character scalar - the Info-dictionary key.

Value

Character scalar, UTF-8 encoded. "" if the tag is not present.

See also

pdf_doc_info() for a single call that returns every standard tag plus the page count and file version.

Examples

fixture <- system.file("extdata", "fixtures", "shapes.pdf",
  package = "pdfium"
)
if (nzchar(fixture)) {
  doc <- pdf_doc_open(fixture)
  pdf_doc_meta(doc, "Producer")
  pdf_doc_close(doc)
}