Alarm?

Ruby
1

Hello,

I see that there is a Signal class in the core for catching signals.
Where
would the alarm system call be, for setting a SIGALRM? I can’t seem to
find
it.

Thanks,
Mike

2

On Mon, Sep 25, 2006 at 10:55:19AM +0900, Michael P. Soulier wrote:

Hello,

I see that there is a Signal class in the core for catching signals. Where
would the alarm system call be, for setting a SIGALRM? I can’t seem to find
it.

% cat alarm.rb
trap(“ALRM”) do
puts “Alarm!”
end

Process.kill(“ALRM”, $$)

% ruby alarm.rb
Alarm!

HTH.

3

On 25/09/06 Logan C. said:

% cat alarm.rb
trap(“ALRM”) do
puts “Alarm!”
end

Process.kill(“ALRM”, $$)

% ruby alarm.rb
Alarm!

But that doesn’t tell the OS to send a SIGALRM at a predefined time.
I’ve
found the timeout library, and implemented what I needed with that, but
isn’t
the alarm() system call exposed in Ruby? It is in Perl and Python.

Thanks,
Mike

4

On 25/09/06 Logan C. said:

dlload “libc.#{so_ext}”
loop {}

% ruby alarm.rb
Alarm!

Impressive that you could write this so quickly. Still, shouldn’t this
be in
the standard library? I certainly don’t want to do this with all of
POSIX. :slight_smile:

Thanks,
Mike

5

On Mon, Sep 25, 2006 at 08:21:44PM +0900, Michael P. Soulier wrote:

But that doesn’t tell the OS to send a SIGALRM at a predefined time. I’ve
found the timeout library, and implemented what I needed with that, but isn’t
the alarm() system call exposed in Ruby? It is in Perl and Python.

Thanks,
Mike
Oops, sorry misunderstood the question. Is this better?
% cat alarm.rb
require ‘dl/import’
module Alarm
extend DL::Importable
if RUBY_PLATFORM =~ /darwin/
so_ext = ‘dylib’
else
so_ext = ‘so’
end
dlload “libc.#{so_ext}”
extern “unsigned int alarm(unsigned int)”
end

trap(“ALRM”) do
puts “Alarm!”
exit
end

Alarm.alarm(3)

loop {}

% ruby alarm.rb
Alarm!