Hi,
This technique was a very common one in assembler sources for PDP-11
versions of UNIX. For example, m40.s of Version 6 UNIX shows a line
"jsr r0,call1; _trap" in its trap routine. I feel very funny to
tell this to Warren, the author of apout!
Anyway, it could be a source of the null-terminated expression of
character strings of the C language, I guess.
Naoki Hamada
nao(a)tom-yam.or.jp