Jean Delvare wrote: > On Mon, 22 Oct 2007 15:15:51 +0200, Hans de Goede wrote: >> Jean Delvare wrote: >>> On Mon, 22 Oct 2007 11:40:11 +0200, Hans de Goede wrote: >>>> I've also added a comment how to use it in future versions. The idea is to >>>> increment the lower digit when for example new features are added to the >>>> featuretype enum, so that applications can check the SENSORS_API_VERSION and >>>> conditionally support new features for example (if they don't/can't check they >>>> will no longer compile against an older libsensors). >>> I think I wouldn't have bothered. If applications no longer compile >>> with an older libsensors, then just upgrade libsensors. >> That would mean much pain for distro developers which want to minimize churn, >> but may still need to upgrade an application because of security reasons. > > My experience is that distributions backport fixes for security bugs, > rather than upgrading to the next version of the application or the > library. But I don't actually think this is the right way to do it, so > I'll buy your argument :) > Well Fedora as a fast moving distro usually upgrades rather then backports. >> Well with mine one can do: >> #if (SENSORS_API_VERSION / 100) == 4 >> >> But I'm fine with either. > > Ah right, I tend to forget that >> is nothing more than a division ;) > But... still, I think I'd feel more confident if we used hexadecimal. > Ok, changed to hexadecimal >>> Another thing: don't you want to define SENSORS_API_VERSION in trunk as >>> well? If not, you'll always have to test for SENSORS_API_VERSION's >>> existence before checking its value. I know that versions up to and >>> including 2.10.4 do not have the define and we can't change that, but >>> maybe applications will want to support all versions >= 2.10.5 so that >>> the #if magic can be limited to something sane. >> Not necessary, if an identifier which is not a MACRO gets used in an #if >> statement it is considered zero, so to take you example: >> #if (SENSORS_API_VERSION / 100) == 4 >> >> Would expand to: >> #if (0 / 100) == 4 >> >> And thus be false. > > Unless the application is built with -Wundef (which is our case now), > in which case a warning is issued. That's what I would like to avoid. > Ok, added to trunk, with an initial value of 0x300 Regards, Hans
