Alarm?

ruby-talk
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

···

--
Michael P. Soulier <msoulier@digitaltorque.ca>
"Any intelligent fool can make things bigger and more complex... It
takes a touch of genius - and a lot of courage to move in the opposite
direction." --Albert Einstein

2

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

Process.kill("ALRM", $$)

% ruby alarm.rb
Alarm!

HTH.

···

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.

3

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

···

On 25/09/06 Logan Capaldo said:

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

Process.kill("ALRM", $$)

% ruby alarm.rb
Alarm!

--
Michael P. Soulier <msoulier@digitaltorque.ca>
"Any intelligent fool can make things bigger and more complex... It
takes a touch of genius - and a lot of courage to move in the opposite
direction." --Albert Einstein

4

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!

···

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

5

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

···

On 25/09/06 Logan Capaldo said:

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!

--
Michael P. Soulier <msoulier@digitaltorque.ca>
"Any intelligent fool can make things bigger and more complex... It
takes a touch of genius - and a lot of courage to move in the opposite
direction." --Albert Einstein