XmStringGetNextSegment(3) on Linux
The text a33b6a8f3f24, 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 fetches the bytes in the next segment of a compound string "XmStringGetNextSegment" "compound string functions" "XmStringGetNextSegment"