What does it mean when you check on "Recursive" in Header Search Paths

Question

I've been referencing a lot of Projects, and i do it through adding their paths in Header Search Paths.

I've been following the referencing stuffs through the "Referenced Project's" getting Started (like for example including the ZXingWidget).

And I've been doing it a lot now, but I don't understand the checking of recursive.

1. What does this mean?
2. When do I check a path for "recursive?"

Thanks

Answer 1

If you give Xcode a path to use for headers, it will check that path when you use an #include or #import statement. If the file isn't there, it quits.

If you have the path set as "recursive", Xcode will search folders it finds there if it doesn't find the file.

Looks like this:

Answer 2

1) Enter your desired path for Header Search Paths, click enter.

2) Double click the path text that you entered.

3) On the right of the dialog box select recursive.