Re: add libssh.pc for pkg-config?

["Bernhard R. Link" <brlink@xxxxxxxxxx>]

* Vic Lee <llyzs@xxxxxxx> [091030 13:51]:
> Yes I agree it's easier to link with -lssh, but it won't be that easy to
> check if the version is >= 0.4. For example, currently I can do this by
> checking a new API only in 0.4 like this:
>
> AC_CHECK_LIB(ssh, ssh_option_set, [echo you have 0.4], [echo you have
> old version of you don't have libssh at all])
>
> with libssh.pc I can simply say:
>
> PKG_CHECK_MODULES(SSH, libssh >= 0.4)

The autoconf ideology is "test what you need instead on where you are",
which here would extend to "do not check the version but if the
functions you want to use are there".
There are arguments for both sides with versions. From my experience I
vastly prefer checking for the newest function you use. Otherwise one
always have tests that still pass while the library changed so much it
no longer works or checks failing while it would totally work with the
currently installed library.

> So this is really the point. But I also agree this could be a packing
> issue. But as Bernhard said in the previous email, we should really
> consider to keep *at least* source compatibility for future version,
> since 0.4. Of course binary compatibility is even better, but I think
> people can live without it. :)

From what I read on irc, I was under the impression, 0.5 was supposed to
be the one starting a stable API. When this starts is not that much
important, as long as there will be a mostly stable API someday and that
day is soon enough that there are not any large legacy projects using it
where noone is volunteering to port them to the new version.

> By the way, I am using both Debian and Ubuntu, and the libssh-3 package
> simply conflict and replace libssh-2 in their repository. I bet they
> will do the same thing when packaging libssh 0.4 - conflict+replace 2&3.

Ahem, libssh-2 and libssh-3 do not conflict. libssh-2-dev and the new
libssh-dev conflict. The library packages itself are coninstallable
(though as coming from the same source, no distribution will contain
both, but the user can still have both installed (and usually will at
least during an upgrade between distributions)).

Hochachtungsvoll,
	Bernhard R. Link
-- 
"Never contain programs so few bugs, as when no debugging tools are available!"
	Niklaus Wirth