Eric Blake wrote: > I was going off of the POSIX 200x draft copy, where they were given OB > shading (ie. a future version of POSIX may withdraw support for them).
Sure. But that POSIX 200x draft still describes 'setjmp' as having unspecified behaviour w.r.t. signal mask. They are calling _setjmp "obsolescent", but at the same time the only non-"obsolescent" to achieve the same thing - sigsetjmp(.,0) - is always slower than _setjmp. Someone is not doing his job right here: either the Austin group, or the system implementors. > Rather, the question (which you should > probably take up with the Austin group) is whether bypassing the signal > mask is safe enough to keep without obsoletion, and in which use cases. There is no question here. sigsetjmp(.,0) is in the standard, and not "obsolescent". If that is "safe", _setjmp is equally "safe". > It is certainly NOT safe for use in signal handlers. Sure, but that's not its main use-case. > I have no disagreements that _setjmp is still the only documented way to > save context without wasting time on signal masks, nor that it is likely > faster than sigsetjmp(,0). Can you then please fix the gnulib doc to not be so negative about _setjmp/ _longjmp? I propose: A future revision of POSIX later than the 2008/2009 one may drop the functions _setjmp and _longjmp. Still, in 2008, on all systems which have _setjmp, it is the fastest way to save the registers but not the signal mask. Bruno
