XmStringLineCount(3) on Linux
The text a07503e04795, as Debian 13 (Trixie), Debian 12 (Bookworm), Debian 11 (Bullseye), Debian 10 (Buster), Debian 9 (Stretch), Debian 8 (Jessie) shipped it.
A compound string function that returns the number of separators plus one in the provided compound string "XmStringLineCount" "compound string functions" "XmStringLineCount"