poll (3) (WAS select (3))

[Kaare Rasmussen]

Den 30-04-2016 kl. 19:14 skrev Kaare Rasmussen:

select(3) is an abysmal API. There's a reason most OSes replaced 
select(2) with a backward compatibility select(3) and moved on to 
something poll-like (look for poll(2) or epoll(2)).


Well, it's not that I fare better with poll. This segfaults on the line 
containing 'note $a.perl;'

I'll put it away for now. Time's up.

/kaare

#!/usr/bin/env perl6

use NativeCall;

class Pollfd is repr('CStruct') {
    has int32 $.fd;
    has int16 $.events;
    has int16 $.revents;
}

constant POLLIN            = 0x001;
constant POLLPRI        = 0x002;
constant POLLOUT        = 0x004;

constant POLLRDNORM        = 0x040;
constant POLLRDBAND        = 0x080;
constant POLLWRNORM        = 0x100;
constant POLLWRBAND        = 0x200;

constant POLLMSG        = 0x400;
constant POLLREMOVE        = 0x1000;
constant POLLRDHUP        = 0x2000;

constant POLLERR        = 0x008;
constant POLLHUP        = 0x010;
constant POLLNVAL        = 0x020;

sub poll(CArray[Pollfd], uint64, uint32) returns int32 is native { * }

my $timeout = 5000;
my @readfd := CArray[Pollfd].new(
    Pollfd.new(fd => 1, events => POLLIN, revents => 0),
);

note @readfd.WHERE;
note poll(@readfd, @readfd.elems, $timeout);
note @readfd.WHERE;
note 'xx';
my $a = @readfd[0];
note 'xy';
note $a.WHAT;
note $a.perl;