Noticed an interesting GUI based setting in MacVim, that seems useful but I can't seem to find any official word on what it does exactly.
It is located at Edit Menu > Global Settings > Search Path...
Once there a dialog drops down with the following:
"Enter search path for files"
Separate directory names with a comma.
.,/usr/include,,
From that editable line I get the clue that this appears to be a header search path. Something I would hope works with ctags, etc. But the setting I put in there don't seem to stick between open and closing just MacVim windows with out even quitting the MacVim Application.
Searing Vim help only really turns up new-search-path which I am not sure how to use or set if it is even related?
Is this what I think it is? The header search path. If yes then how do I set the path in my .vimrc or where needed so that the changes to it are persistent.
If this is not a header search path then what does it do?
I think you are right about its purpose, the setting is simply called path: its default value (:set path?) is .,/usr/include,, just as in your question.
You can use it to tell Vim to look for files in specific places.