Re: Getting rid of the mandb profile hook?

[Brice Waegeneire <brice@waegenei.re>]

Hello Ludovic,

On 2021-03-03 15:13, Ludovic Courtès wrote:
>>> I’m thinking we could get rid of the mandb hook.  However, the
>>> functionality matters IMO (we need good tools so users can browse 
>>> local
>>> documentation; mandb is not that good but better than no search
>>> mechanism.)  Here are several options that come to mind:
>>> 
>>>   1. Provide a ‘man’ wrapper or modify the ‘man-db’ package such that
>>>      the database gets built on the first use of ‘man -k’, unless 
>>> it’s
>>>      already up-to-date.
>> 
>> That would mean the database would live in some user-specific writable
>> area of the file system correct (where?), right?  And could use the
>> common 'update' mechanism of man-db to make it as fast as possible.
>> 
>> This sounds good from a performance perpective, but could introduce
>> cache issues every now and then (if man-db changes a lot).  I wouldn't
>> expect much problem given how mature man-db is, but that's one thing 
>> to
>> consider.
> 
> I looked a bit at man-db, thinking it must have that already done more
> or less.  Indeed, one can run “mandb -uc” to create the database.
> 
> The problem is that it insists on writing databases and ‘CACHEDIR.TAG’
> files in the same directory as man pages.  In our case, these are all
> read-only, so just prints a warning for each directory and keeps going.
> 
> It looks like man-db is not written with a situation like ours in mind.

What about using mandoc¹, the manpage compiler from OpenBSD, instead of
man-db? As from it's manual it support specifying the database location:

“makewhatis -d dir [file ...]”²

It isn't packaged in Guix yet, but other Linux distros have done it, 
some
  are even using it as their default.

> [...]
> 
> One option I contemplated at one point is to simply have fewer man 
> pages
> in the first place.  :-)  There were packages that install man pages
> when they shouldn’t.  This led to commits like
> 305eefc0627eb1d047e6fc4320d7e56897719ab8 and
> 4b797193d7508ddc53bb1ff7a267a0d50c1fe298 (and parent commits).

More outputs would be great tho having a way to force the installation 
of
specifics outputs for every installed package would improve quality of
live.  For a specific example in that case, when installing ncurses from
  the cli it would install it's man output too if you always want man 
page
  to be installed.

¹ https://mandoc.bsd.lv/
² https://www.mankier.com/8/makewhatis.mandoc

Cheers,
- Brice