HP-UX Reference (11i v1 05/09) - 2 System Calls (vol 5)

select(2) select(2)

* Set num_of_fds to the required value.

* User can set it to the maximum possible value the kernel is

* configured for, by using sysconf(_SC_OPEN_MAX).

* Note that, if you are not using these many files, you are

* wasting too much space.

num_of_fds = sysconf(_SC_OPEN_MAX);

s = sizeof(long);

* howmany is a macro defined in sys/types.h

f = (struct fd_set *)malloc(s*howmany(num_of_fds, s*8);

* Use f wherever struct fd_set * is used.

* It can be used to test num_of_fds file descriptors.