To let a process obtain the band and event associated with SIGPOLL more readily, STREAMS supports extended signals. For the given events, a special code is defined in <sys/siginfo.h> that describes the reason SIGPOLL was generated. Table 3-5 describes the data available in the siginfo_t structure passed to the signal handler.
Table 3-5 Data in siginfo_t Structure
Event |
si_signo |
si_code |
si_band |
si_errno |
---|---|---|---|---|
S_INPUT
|
SIGPOLL |
POLL_IN |
Band readable |
Unused |
S_OUTPUT |
SIGPOLL |
POLL_OUT |
Band writable |
Unused |
S_MSG |
SIGPOLL |
POLL_MSG |
Band signaled |
Unused |
S_ERROR |
SIGPOLL |
POLL_ERR |
Unused |
Stream error |
S_HANGUP |
SIGPOLL |
POLL_HUP |
Unused |
Unused |
S_HIPRI |
SIGPOLL |
POLL_PRI |
Unused |
Unused |