On Thu, May 30, 2013 at 10:02:10PM +0200, Olaf Hering wrote: > > libguestfs and supermin use 'no' instead of either the basename of the > desired application, or 'false', as helper string. This happens when > configure does not find things like rpm or supermin during build. > > Wouldnt it be more logical to use the basename instead of 'no' so that > at runtime one has the chance to install the required packages and in > addition get an obvious error message in verbose mode what external > helper is actually missing? In my package I force a few things like > 'export ZYPPER=zypper' to avoid the unneeded BuildRequires: zypper. But > doing that for every binary that maybe called is cumbersome. > > I think its best to rely on PATH to let libguestfs and supermin packages > find their external helpers at runtime. And one who has a need to > actually hardcode absolute paths to external helpers into his > libguestfs/supermin binaries can do that by doing the 'export > HELPER=/path/to/helper' during his own configure run. > > Thoughts?
I suspect it depends on the application on a case-by-case basis. Examples (from libguestfs): - supermin-helper: This is called at runtime. If not found at compile time it's currently set to 'no' which AFAICT leads to a binary build that could never work except with a fixed appliance [fixed appliance doesn't need supermin-helper]. This is a bug, I think. - msgmerge: If not present, localization is disabled. It doesn't really make sense to enable this "at runtime". - db_dump: We conditionally compile some inspection support based on whether db_dump is found or not. This may or may not be a bug, depending on whether you think it's worth inspection carrying around a lot of code that has to be tested in the db_dump present/not-present- at-runtime cases. Also the runtime code would have to check for every variation of db_dump, because it has lots of different names. So I think patches are welcome, but they'll have to be reviewed individually. Rich. -- Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones virt-top is 'top' for virtual machines. Tiny program with many powerful monitoring features, net stats, disk stats, logging, etc. http://people.redhat.com/~rjones/virt-top _______________________________________________ Libguestfs mailing list [email protected] https://www.redhat.com/mailman/listinfo/libguestfs
