GNU texinfo directory search method?

Question

Does info (GNU texinfo 4.13) have a default search path for finding a dir file? Is it /usr/share/info? Even though I don't have an INFOPATH variable set in my environment, it seems to use the dir file in the path above.

Relatedly, I have a script that sets up a directory with an alternate info directory structure. It does set a valid INFOPATH environment variable but info seems not to use it as invocation simply gives a blank screen without any menu items.

Any guidance on how info progresses in searching the path?

Answer 1

Yes, info does have a default value for INFOPATH compiled-in that it uses if you don't have INFOPATH set in your environment. (Also, if your INFOPATH ends with a colon, then the default path is appended to your value.)

The default DEFAULT_INFOPATH is .:/usr/local/info:/usr/info:/usr/local/lib/info:/usr/lib/info:/usr/local/gnu/info:/usr/local/gnu/lib/info:/usr/gnu/info:/usr/gnu/lib/info:/opt/gnu/info:/usr/share/info:/usr/share/lib/info:/usr/local/share/info:/usr/local/share/lib/info:/usr/gnu/lib/emacs/info:/usr/local/gnu/lib/emacs/info:/usr/local/lib/emacs/info:/usr/local/emacs/info (but it can be changed by defining DEFAULT_INFOPATH while compiling info).

There's also a INFODIR variable that can be set while compiling info. If set, it gets included in the path after the INFOPATH environment variable but before the DEFAULT_INFOPATH.

I don't know any way of asking your info program what values it was compiled with. (Although you can probably find the actual value of DEFAULT_INFOPATH with this command:)

strings `which info` | grep /info:

Answer 2

The search order that info is taking to find files and nodes can be examined by invoking it with the various --debug options (--debug -1 for all debug info).

For example

INFOPATH=: info --debug -1 _

will print out all the paths derived from $PATH, followed by all the compile-time defaults.