This is the mail archive of the cygwin-developers mailing list for the Cygwin project.
Index Nav: | [Date Index] [Subject Index] [Author Index] [Thread Index] | |
---|---|---|
Message Nav: | [Date Prev] [Date Next] | [Thread Prev] [Thread Next] |
Other format: | [Raw text] |
On 10/27/2012 04:25 AM, Corinna Vinschen wrote: > On Oct 26 12:52, Eric Blake wrote: >> On 10/26/2012 12:29 PM, Corinna Vinschen wrote: >>> If there's no reason to keep space, I would opt for this implementation: >>> >>> #ifdef __x86_64__ >>> #define NSIG 65 /* signal 0 implied */ >>> #else >>> #define NSIG 33 /* signal 0 implied */ >>> #endif >>> >>> /* Real-Time signals per SUSv3. RT_SIGMAX in limits.h has to agree. */ >>> #define SIGRTMIN 32 >>> #define SIGRTMAX (NSIG - 1) >>> >>> It's not dynamic, but it doesn't seem to make a lot of sense to make it >>> dynamic. Even in the 32 bit case, if we change the number of available >>> RT signals it can also occur together with the ABI change, so an old >>> application would still have the old number of RT signals, despite any >>> effort to make the number dynamic. Me thinks. >> >> Seems reasonable to me - if there is ever a new signal added, we'd also > > I don't quite understand. The joke here is that the above would NOT allow > to add any further signal. Ever. Except for more RT signals in the 32 > bit case. What am I missing? If we ever add a new signal, it would be an ABI change - code compiled against old cygwin.dll would call into the old ABI, where there are 32 or 64 total signsl with 1 or 33 RT signals and no access to the new signal; new code would call into the new ABI where there are 64 total signals (even on 32-bit cygwin) and the new signal has been carved out appropriately. That is, the cost of adding a new signal for 32-bit cygwin is an ABI change, but if we do the ABI change, we can also do it for 64-bit cygwin at the same time. But I think this is theoretical - we are unlikely to add a new signal, so go with the above definition without worrying about it. -- Eric Blake eblake@redhat.com +1-919-301-3266 Libvirt virtualization library http://libvirt.org
Attachment:
signature.asc
Description: OpenPGP digital signature
Index Nav: | [Date Index] [Subject Index] [Author Index] [Thread Index] | |
---|---|---|
Message Nav: | [Date Prev] [Date Next] | [Thread Prev] [Thread Next] |