Summary - lost of SIGIO signal in SunOS4.1/4.0.3

[Guy Harris]

>>I know nothing about the various Sun OSs. However, UNIX System V Release 4
>>does provide both reliable signals *and* the capability of queueing them.
>
>Queueing, or regenerating?  I will bet it is `regenerate':

And I will bet it's "queue"; S5R4 will, if SA_SIGINFO is specified when
the signal is caught with "sigaction()", pass, as two additional
arguments to the signal handler, a pointer to a "siginfo_t" structure
containing various information (a generalization of the BSD "code"
argument, plus the SunOS 4.x "addr" argument, containing other stuff -
e.g.  the child process ID and exit status for SIGCHLD) and a pointer to
a "ucontext_t" structure (similar to the BSD "context" argument).