1:      1  1 CALL pred list_cmd.main/2-0 (det) list_cmd.m:22
mdb> echo on
Command echo enabled.
mdb> list_cmd ./list_cmd.sh
mdb> step
       2:      2  2 CALL pred list_cmd.fib/2-0 (det) list_cmd.m:29 (list_cmd.m:23)
mdb> list
mdb: ./list_cmd.sh: posix_spawn not supported on this platform
mdb> continue -n
8