Re: [install info (using perl) 1/2] Add support for an info version of the user manual

[David Kastrup <dak@gnu.org>]

Junio C Hamano <gitster@pobox.com> writes:

> David Kastrup <dak@gnu.org> writes:
>
>> +git.info: user-manual.xml
>> +	$(RM) $@ $*.texi
>> +	$(DOCBOOK2X_TEXI) user-manual.xml --to-stdout | \
>> +	perl -ne 'if (/^\@setfilename/) {$$_="\@setfilename git.info\
>> +"} elsif (/^\@direntry/) {print "\@dircategory Development\
>> +\@direntry\
>> +* Git: (git).           A fast distributed revision control system\
>> +\@end direntry\
>> +"} print unless (/^\@direntry/ .. /^\@end direntry/)' > $*.texi
>> +	$(MAKEINFO) --no-split $*.texi
>> +	$(RM) $*.texi
>> +
>
> This part worries me.
>
> Historically (as you probably know, having suffered a lot more
> than me with this issue), multi-line command script in Makefile
> was hugely unportable.  Some "make" implementations stripped
> backslash linefeed at the end, some other implementations
> stripped only backslash, yet some other kept both backslash and
> linefeed.  It was a mess.
>
> Admittably we are already quite dependent on GNU make,

Yes, definitely.  That's why I did it that way in the first place.  It
is probably not inconceivable, however, that even then some
combination of make port and perl port to Windows would get into a
tizzy.

> so this is probably not a huge deal, but I have a vague recollection
> that even GNU make itself changed its behaviour over time with
> respect to this exact area, and I had to adjust a few Makefiles to
> accomodate both old and new GNU make.

I have to admit that I did not know in advance how this would work out
and adapted the code to the behavior.

> The standard workaround is of course to have this perl script
> part as a separate, "Documentation/fixup-texi.perl" script and
> invoke it from the Makefile.

I can code this as a single overlong line reasonably easy.  And it is
not actually necessary to do the @setfilename replacement: one can
just specify an override of the output file name.  That shortens the
Perl script.  I'll have to see whether I can get rid of it completely,
but the documentation for docbook2X is really bad (and the author did
not respond to Email yet).  And googling on the net showed that I am
not the only one who fixed up after docbook2X manually.

Don't expect a new patch in this area soon: I am messing with other
stuff right now and it does not make sense reworking this again when I
am not sure yet whether I can throw it out altogether.

-- 
David Kastrup, Kriemhildstr. 15, 44793 Bochum