# SIGTERM signal is ignored by a process run using Ruby

**URL:** <https://www.ruby-forum.com/t/sigterm-signal-is-ignored-by-a-process-run-using-ruby/121650>\
**Category:** Ruby\
**Created:** [November 29, 2007, 5:17pm UTC](https://www.ruby-forum.com/t/sigterm-signal-is-ignored-by-a-process-run-using-ruby/121650 "2007-11-29T17:17:09Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![luca](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/l/51bf81/32.png) [@luca](https://www.ruby-forum.com/u/luca)\
**Post date:** [November 29, 2007, 5:17pm UTC](https://www.ruby-forum.com/t/sigterm-signal-is-ignored-by-a-process-run-using-ruby/121650/1 "2007-11-29T17:17:09Z")

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Hello Everybody,  
I am using Ruby 1.8.5 in a Rails 1.2.5 environment.  
My code starts a dhcp-3.1.0 service taken from  
[http://www.isc.org/products/DHCP](http://www.isc.org/products/DHCP)  
Once started the dhcpd process cannot be stopped using the normal  
“/etc/init.d/dhcp stop”  
as it seems not to catch SIGTERM (signal 15) used within the service  
script.  
Can anyone help me, as it is 2 days I am unusefully fighting ?  
Thank you in advance,  
Luca

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<div class="post-metadata">

**Author:** ![luca](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/l/51bf81/32.png) [@luca](https://www.ruby-forum.com/u/luca)\
**Post date:** [November 29, 2007, 6:37pm UTC](https://www.ruby-forum.com/t/sigterm-signal-is-ignored-by-a-process-run-using-ruby/121650/2 "2007-11-29T18:37:19Z")

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On Nov 29, 2007, at 9:17 AM, Luca Boero wrote:

> ## Luca
> 
> Posted via [http://www.ruby-forum.com/](http://www.ruby-forum.com/).

no offense - but this doesn’t have anything to do with ruby does it?  
the dhcp script is normally a /bin/sh script and i assume yours it too?

if not, and it’s ruby - modify the call the ‘trap’ so SIGTERM is not  
caught.

if it is /bin/sh, and SIGTERM is trapped, you will have to figure out  
which signal to send. Process.kill(-9, pid) will work, but i’d  
strive to understand _why_ dhcp prefers to trap SIGTERM and determine  
how it is supposed to be shut down. if there is no correct way file  
a bug with the maintainers of that code.

regards.

a @ [http://codeforpeople.com/](http://codeforpeople.com/)

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<div class="post-metadata">

**Author:** ![luca](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/l/51bf81/32.png) [@luca](https://www.ruby-forum.com/u/luca)\
**Post date:** [February 22, 2008, 9:08am UTC](https://www.ruby-forum.com/t/sigterm-signal-is-ignored-by-a-process-run-using-ruby/121650/3 "2008-02-22T09:08:53Z")

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Luca Boero wrote:

> I am using Ruby 1.8.5 in a Rails 1.2.5 environment.  
> My code starts a dhcp-3.1.0 service taken from  
> [http://www.isc.org/products/DHCP](http://www.isc.org/products/DHCP)  
> Once started the dhcpd process cannot be stopped using the normal  
> “/etc/init.d/dhcp stop”  
> as it seems not to catch SIGTERM (signal 15) used within the service  
> script.

here’s a late confirmation: this is definitely a bug in ruby 1.8.5,  
which looks like it’s fixed in 1.8.6.

here’s a small test program to verify if you have the bug:

previous\_handler = trap(‘TERM’) { raise RuntimeError, “signal” }  
puts “prev handler:”  
puts previous\_handler  
myhandler = trap(‘TERM’, previous\_handler)  
puts “temp handler:”  
puts myhandler  
nhandler = trap(‘TERM’, previous\_handler)  
puts “handler after restore:”  
puts nhandler

puts `echo test self-kill; kill $$; echo should not get here, that is a bug`

trap(‘TERM’, “DEFAULT”)  
defhandler = trap(‘TERM’, “DEFAULT”)  
puts “handler should be default, is:”  
puts defhandler

correct output would look like this:

prev handler:  
DEFAULT  
temp handler:  
#Proc:removed\_email\_address@domain.invalid:2  
handler after restore:  
DEFAULT  
test self-kill  
handler should be default, is:  
DEFAULT

but when I test it on 1.8.5 I get this instead:

prev handler:  
nil  
temp handler:  
#Proc:removed\_email\_address@domain.invalid:2  
handler after restore:  
IGNORE  
test self-kill  
should not get here, that is a bug  
handler should be default, is:  
nil

- Arne H. J.