Returns the signing time as the raw PDF date string
("D:YYYYMMDDHHmmSS+HH'mm'"). Empty if the signature defers to
the PKCS#7 timestamp. Pass to pdf_parse_date() for POSIXct.
Wraps FPDFSignatureObj_GetTime.
Arguments
- sig
A
pdfium_signaturehandle frompdf_signatures().