🚀 go-pugleaf

In article <1992Oct1.085838.7536@rulway.LeidenUniv.nl>, rekers@elc2 (Jan Rekers) writes:
|> 
|> I am new into LOTOS and I have just worked my way through the
|> introduction in LOTOS by Bolognesi and Brinkman.  Now, on trying to
|> use LOTOS, I have encountered a problem which is very basic to my
|> understanding of the formalism. I would appreciate any help with the
|> following:
|> 
|> I wish to define a ring of processes with the following layout:
|> 
|>                      1
|>                     / \
|>                    c   a
|>                   /     \
|>                  3 - b - 2
|> 
|> 1, 2 and 3 are processes; a, b and c are actions.
 
You can specify this in LOTOS:

   hide a, b, c in
     (node[c,a](1) |[a]| node[a,b](2))
   ||
     node[b,c](3)


However, the ring is a deadlock since 2 is waiting for 1,
3 for 2, and 1 for 3.

You need something to kick off the ring, such as:

   hide a, b, c in
    ( (a; node[c,a](1)) |[a]| node[a,b](2))
  ||
    node[b,c](3)