pselect: Use linux pselect syscall when available

Linux has a pselect syscall since 2.6.something. Using it
rather than emulating it with sigprocmask+select+sigprocmask
is smaller code, and works properly. (The emulation has
race conditions when unblocked signals arrive before or
after the select)

The tv.nsec >= 1E9 handling comes from uclibc's linux select()
implementation, which itself uses pselect() internally if the
pselect syscall exists. I though it would be good to do the
same here.

Note that although the libc pselect() API has 6 arguments,
the linux kernel syscall as 7 arguments. There is an extra,
somewhat vestigial, sizeof the signal mask argument.

Signed-off-by: Nicolas S. Dade <nic.dade@gmail.com>

0 files changed, 0 insertions, 0 deletions