mod_sasl2_fast: Improve handling when SASL profile unexpectedly lacks CB
This fixes a traceback reported by riau, but likely does not solve the
underlying cause, whatever that is.
---
summary: Set process name to prosody
...
This module sets the process name to `prosody` so it shows up as such
instead of `lua` in process management tools.
To use this module, you'll need the proctitle Lua library:
<https://github.com/hoelzro/lua-proctitle>