pdfGetAnnot). Only some annotation types have content;
pdfGetAnnotContentwill return NULL for annotations that don't have content.
A string is returned, and
*length is filled in with the
string length. The string will be zero-terminated, but it may contain
zero bytes, depending on the current text encoding (see
pdfSetTextEncoding). The caller is responsible for freeing the
string (if non-NULL) with the