On Jul 9, 2009, at 5:13 PM, Enling Li wrote:

> I have another quetion related to fire off a back ground shell process
> on a remote Linux.
>
>    require "net/ssh"
>
>    ssh = Net::SSH.start( '10.0.77.87', 'toor',  :password=>'logapp')
>    ssh.exec!("/root/test.pl &")
>    ssh.close
>    puts "I want to be here immediately, but not"
>
> The above code hangs also because test.pl contains a long sleep and do
> nothing. Can someone offer me a help?
>
> Thank you in advance.
>
> Enling
>
> Stephen Bannasch wrote:
>> I want to start a Java program from a Ruby program and have the Java
>> program run in another process and have control returned to my Ruby
>> program as soon as the Java process starts up successfully.
>>
>> I can do this from a shell by suffixing an '&':
>>
>>   java -cp <classpath> <main_class>&
>>
>> starts the Java program in a background process thread and returns
>> control the shell.
>>
>> When I try this from a Ruby program the program blocks until the Java
>> program is terminated.

If your system has the `setsid` (set session id) program (and the  
underlying system call), then you could try:

   ssh.exec!("setsid /root/test.pl")

or

   setsid java -cp YOURCLASSPATH MainClass

but you may wish to redirect output.

   ssh.exec!("setsid /root/test.pl >/tmp/test.log 2>&1")

-Rob

Rob Biedenharn		http://agileconsultingllc.com
Rob / AgileConsultingLLC.com