[systemd-devel] feature request: dlopen

[Cameron Norman]

On Sun, Feb 22, 2015 at 4:52 PM, Zbigniew Jędrzejewski-Szmek
<zbyszek at in.waw.pl> wrote:
> On Sun, Feb 22, 2015 at 11:58:25PM +0000, Luke Kenneth Casson Leighton wrote:
>> On Wed, Feb 18, 2015 at 9:10 AM, Tobias Hunger <tobias.hunger at gmail.com> wrote:
>> > Hi Luke,
>> >
>> > I am mostly a lurker on the systemd mailing list, so my opinion does
>> > not carry weight in this community.
>> >
>> > On Tue, Feb 17, 2015 at 9:24 PM, Luke Kenneth Casson Leighton
>> > <lkcl at lkcl.net> wrote:> so i'm not going to "protest" - i'm going to
>> > try a different approach.
>> >> i'd like you to look at this list of debian packages that are
>> >> dependent on libsystemd0:
>> >> http://lkcl.net/reports/removing_systemd_from_debian/list_of_libsystemd0_dependent_packages.txt
>> >
>> > I understood most of these dependencies to be indirect: Packages that
>> > depend on other packages that in turn depend on libsystemd. Is that
>> > correct?
>>
>>  that's right.  so, what that means is that the actual number of
>> packages which would need to be converted to dynamic loading is
>> actually very small (about 100), and the remaining 4,483 would be fine
>> (not need any work done on them at all).
>>
>>
>> > On the other hand the library is tiny and basically falls back to
>> > being a no-op in the case where systemd is not PID1, so it does not
>> > hurt non-systemd systems to have this library in any way.
>>
>>  ...except that its introduction (usually --with-libsystemd) in those
>> 100 (or so) packages has been done in a mutually-exclusive,
>> hard-compile-time switch that *excludes* the possibility of dynamic
>> (runtime) decision-making.
> I think this is the crux of the matter. Please accept the fact that
> this compile time switch does not preclude runtime decision making at
> all. When not running under systemd, calls into libsystemd degrade
> into silent noops. So they only "cost" that is an extra unused 600kb
> library, which is completely insignificant.

And when it is significant you are usually in situation where you are
compiling your own packages and can remove the systemd compile time
option.

--
Cameron Norman