isdnlog(8) on Linux
The text d7323e5599d5, as Debian 3.0 (Woody) shipped it.
isdn log system (and more)
Flags it lists
-
-1 -
-2x -
-Ax -
-Bvbn -
-Rprefix -
-Ux -
-V -
-f -
-ix -
-o -
-ux