AM_MISSING_PROG undocumented

[Eric Blake]

[adding bug-automake, to turn into a formal bug]

On 06/26/2012 11:39 AM, Eric Blake wrote:

> And while looking into how M4 differs from coreutils, I noticed that
> coreutils uses this via a .m4 file included into its configure.ac:
> 
>   AM_MISSING_PROG(HELP2MAN, help2man)
> 
> which is roughly supposed to set $(HELP2MAN) to 'path/to/missing [--run]
> help2man', depending on the version of automake used, without
> hard-coding it as M4 had done.  Maybe M4 could use this trick instead of
> open-coding its use of 'missing --run', but there's a flaw in that plan
> - AM_MISSING_PROG is an undocumented macro, and I'm trying hard to keep
> M4 using only documented interfaces.
> 

AM_MISSING_PROG has been around for a while (git log says it was
introduced in 1997, although the current two-argument version appears to
date back to commit 9ae48df in Nov 1999), and seems like something
stable enough to be worth guaranteeing.

A related suggestion might be to have AM_MISSING_PROG do a filter check
to make sure that the program name being protected by the 'missing'
script is indeed one of the programs that the missing script knows how
to handle in the first place; help2man is in that list.

-- 
Eric Blake   address@hidden    +1-919-301-3266
Libvirt virtualization library http://libvirt.org

signature.asc
Description: OpenPGP digital signature