Info manuals not listed in Termux

Question

I have Emacs installed through Termux. The Emacs manuals (emacs.info.gz, etc.) are located at /data/data/com.termux/files/usr/share/info/. I can open them with find-file. I don't see them with C-h i.

The INFOPATH is set in ~/.bashrc:

# .bashrc
export INFOPATH=$INFOPATH:/data/data/com.termux/files/usr/share/info/

A new Termux session shows the correct INFOPATH. The path above is the Info-default-directory-list and is the last entry in Info-directory-list.

The texinfo, gzip, and zlib packages are installed in Termux.

I can see the manuals for Magit, use-package, etc. listed in *info*.

How can I access the Emacs manuals through Info?

Answer 1

There are two components to the Info system: the info files themselves and a dir file which acts as the top level index. When Info sees more than one directory in INFOPATH, it merges all the dir files that it finds into one index. The corollary however is that the dir file must exist.

You can create the dir file by hand if you want: there is information about that in the Texinfo manual, but in most cases, it is built when the info file for the package is installed.

In any case, since these are the standard emacs info files, you can reinstall them using the appropriate make invocation and get everything. GNU Makefiles make use of the prefix variable (/usr/local by default) to construct all the directories for the software installation. So all you have to do is override that destination:

sudo make install-info prefix=/data/data/com.termux/files/usr

That in turn uses the install-info program appropriately to add the various info files to the dir file in the info directory corresponding to the prefix ($prefix/share/info).

In fact, since the info files were already installed in that directory, the OP found it expedient to just run a small script to create the dir file from the existing info files instead of rerunning the make:

for file in /data/data/com.termux/files/usr/share/info/*
do
     install-info --info-file="$file" --dir-file=/data/data/com.termux/files/usr/share/info/dir
done