How to automatically use a config file located up in a parent directory

[genivia-inc]

Question (in the title) moved from #470 to Q&A here.

Answer

If you want the ug command to tree-walk upward to pick a .ugrep config file located in a parent or ancestor directory, checking all the way up to the home directory, then the following bash alias does the trick:

alias ugh='ug --config="`_wd="$PWD" ; while [[ "$_wd" != "$HOME" ]] ; do if test -f "$_wd/.ugrep" ; then echo $_wd/.ugrep; break; fi ; _wd=${_wd%/*}; done`"'

I picked alias ugh to refer to "UG with inHerited config", but an alias named ug will work too to override the ug command with this alias.

This commands picks a .ugrep config file found in the parent or first ancestor directory, up to the home directory. When you have a .ugrep config file there, then ug will use it.

[genivia-inc]

Note: see the answer in the post above.