1 <assertions> 2 <assertion id="1" tag="def:S:42626:42627 pt:CX"> 3 The sigwait() function shall select a pending signal from 'set', automatically 4 clear it from the system's pending signals, and return that signal number in 5 the location represendted by 'sig'. 6 </assertion> 7 <assertion id="2" tag="def:S:42627:42632 pt:CX"> 8 If prior to the call to sigwait() there are multiple pending instances of a 9 single signal number (and it is implementation-defined that the signal number 10 supports queued signals), then the first such queued signal shall cause a 11 return from sigwait() and the remainder shall remain queued. 12 </assertion> 13 <assertion id="3" tag="def:S:42627:42632 pt:CX"> 14 If prior to the call to sigwait() there are multiple pending instances of a 15 single signal number (and it is implementation-defined that the signal number 16 DOES NOT support queued signals), then there should be no remaining pending 17 signals for that signal number. 18 </assertion> 19 <assertion id="4" tag="def:S:42632:42633 pt:CX"> 20 If no signal in 'set' is pending at the time of the call, the thread shall 21 be suspended until one or more becomes pending. 22 </assertion> 23 <assertion id="5" tag="def:S:42633:42635 pt:CX"> 24 The signals defined by 'set' should have been blocked at the time of the call 25 to sigwait(); otherwise the behavior is undefined. The effect of sigwait() on 26 the signal actions for the signals in 'set' is unspecified. 27 </assertion> 28 <assertion id="6" tag="def:S:42636:42638 pt:CX"> 29 If more than one thread is using sigwait() to wait for the same signal, no more 30 than one of these threads shall return from sigwait() with the signal number. 31 Which thread returns from sigwait() is unspecified if the signal is generated 32 for the process; otherwise only the target thread of the signal can receive the 33 signal. 34 </assertion> 35 <assertion id="7" tag="def:S:42639:42641 pt:RTS"> 36 Should any of the multiple pending signals in the range SIGRTMIN to SIGRTMAX be 37 selected, it shall be the lowest numbered one. The selection order between real 38 time and non-realtime signals, or between multiple pending non-realtime signals is unspecified. 39 </assertion> 40 <assertion id="8" tag="def:S:42642:42645 pt:CX"> 41 Upon successful completion, sigwait() shall store the signal number of the 42 received signal at the location referenced by 'sig' and return zero. 43 </assertion> 44 <assertion id="9" tag="def:S:42642:42645 pt:CX"> 45 Upon unsuccess, sigwait() will return with a non-zero error number to indicate 46 the error. 47 </assertion> 48 <assertion id="10" tag="def:S:42646:42648 pt:CX"> 49 The sigwait() function fails if the 'set' argument contains an invalid 50 or unsupported signal number. 51 </assertion> 52 </assertions> 53
