An error is raised (and the module not unlocked) when trying to unlock a module with a wrong password or when trying to unlock a module locked with lock/1 (error 82).
Success:
[eclipse]: [user].
:- module(m).
:- export p/0.
p :- writeln(hello).
user compiled 60 bytes in 0.00 seconds
yes.
[eclipse]: lock(m, "pass").
yes.
[eclipse]: module(m).
trying to access a locked module in module(m)
[eclipse]: import p/0 from m.
yes.
[eclipse]: p.
hello
yes.
[eclipse]: call(p) @ m.
trying to access a locked module in p
[eclipse]: unlock(m, "pass").
yes.
[eclipse]: call(p) @ m.
hello
yes.
Error:
unlock(M, "pass"). (Error 4).
unlock(m, Pass). (Error 4).
unlock(1, "pass"). (Error 5).
unlock(not_a_module, "pass"). (Error 80).
lock(m, "pass"), unlock(m, "wrong_pass"). (Error 82).
lock(m), unlock(m, "pass"). (Error 82).