pdfEnableBeeps
Enable/disable beeps.
void pdfEnableBeeps(PDFViewerHandle viewer, BOOL on)
Normally, XpdfViewer will emit a beep on various error conditions
(attempting to go to the previous page from page one, attempting to go
to the next page from the last page, a text find string that isn't
found, etc.). This function enables or disables beeps. The default
value is enabled.
C:
pdfEnableBeeps(viewer, FALSE);