cppman -m true fails

[jxu]

Similar to #127 but isn't fixed

I did

touch ~/.manpath
cppman -m true
mandb

warnings

Purging old database entries in /home/jx/.local/man...
Processing manual pages under /home/jx/.local/man...
Processing manual pages under /home/jx/.local/man/cat1...
Purging old database entries in /home/jx/.local/share/man...
Processing manual pages under /home/jx/.local/share/man...
Processing manual pages under /home/jx/.local/share/man/cat1...
Processing manual pages under /home/jx/.cache/cppman...
Updating index cache for path `/home/jx/.cache/cppman/manindex'. Wait...mandb: warning: /home/jx/.cache/cppman/manindex/CACHEDIR.TAG: ignoring bogus filename
mandb: warning: /home/jx/.cache/cppman/manindex/cat3: ignoring bogus filename
mandb: warning: /home/jx/.cache/cppman/manindex/442742: ignoring bogus filename
Updating index cache for path `/home/jx/.cache/cppman/man3'. Wait...done.
Checking for stray cats under /home/jx/.cache/cppman...
Checking for stray cats under /home/jx/.cache/cppman/manindex...
Processing manual pages under /home/jx/.cache/cppman/cppreference.com...
Processing manual pages under /home/jx/.cache/cppman/cplusplus.com...
2 man subdirectories contained newer manual pages.
2527 manual pages were added.
0 stray cats were added.
0 old database entries were purged.

btw $XDG_CACHE_HOME is blank for me

[paopaol]

the same, warning: /root/.cache/cppman/manindex/index.db: ignoring bogus filename.but when i remove this index.db, rerun mandb, then works ok