Creating a filter in YAML fails, complaining of not being able to find various ‘lyaml’ files.

/usr/local/share/lua/5.2/awall/policy.lua:128: module ‘lyaml’ not found:
no field package.preload[‘lyaml’]
no file ‘/usr/local/share/lua/5.2/lyaml.lua’
no file ‘/usr/local/share/lua/5.2/lyaml/init.lua’
no file ‘/usr/share/lua/5.2/lyaml.lua’
no file ‘/usr/share/lua/5.2/lyaml/init.lua’
no file ‘/usr/local/lib/lua/5.2/lyaml.lua’
no file ‘/usr/local/lib/lua/5.2/lyaml/init.lua’
no file ‘./lyaml.lua’
no file ‘/usr/lib/lua/5.2/lyaml.lua’
no file ‘/usr/lib/lua/5.2/lyaml/init.lua’
no file ‘./lyaml.lua’
no file ‘/usr/local/lib/lua/5.2/lyaml.so’
no file ‘/usr/local/lib/lua/5.2/loadall.so’
no file ‘/usr/lib/lua/5.2/lyaml.so’
no file ‘/usr/lib/lua/5.2/loadall.so’
no file ‘./lyaml.so’
stack traceback:
/usr/local/share/lua/5.2/awall/uerror.lua:25: in function
</usr/local/share/lua/5.2/awall/uerror.lua:21>
[C]: in function ‘require’
/usr/local/share/lua/5.2/awall/policy.lua:128: in function ‘init’
/usr/local/share/lua/5.2/awall/class.lua:31: in function
</usr/local/share/lua/5.2/awall/class.lua:29>
(…tail calls…)
/usr/sbin/awall:163: in function ‘f’
/usr/local/share/lua/5.2/awall/uerror.lua:20: in function
</usr/local/share/lua/5.2/awall/uerror.lua:20>
[C]: in function ‘xpcall’
/usr/local/share/lua/5.2/awall/uerror.lua:19: in function ‘call’
/usr/sbin/awall:156: in main chunk
[C]: in ?

(from redmine: issue id 8874, created on 2018-05-11)