Exception for program running on ruby code

Ruby
1

Hello,

I’m trying to get an output from /var/log/syslog for certain amount of
time by executing %x[sudo tail -f /var/log/syslog]

Is it possible to set a timer for the execution, and if the time end,
the execution will end (like we do Ctrl+C) ?

Thank you

2

Ahmad A. wrote:

Hello,

I’m trying to get an output from /var/log/syslog for certain amount of
time by executing %x[sudo tail -f /var/log/syslog]

Is it possible to set a timer for the execution, and if the time end,
the execution will end (like we do Ctrl+C) ?

Thank you

I think I’ve got the solution,

#!/usr/bin/ruby

require ‘timeout’
begin
status = Timeout::timeout(10) do
%x[sudo tail -f /var/log/messages]
end
rescue Timeout::Error
puts ‘execution expired’
end

This might do the job

3

Ahmad A. wrote:

puts ‘execution expired’
end

This might do the job

I don’t think you will get a value in status that way. Try this:

require ‘timeout’

output = []
begin
Timeout.timeout 5 do
IO.popen(“ping 192.168.1.1”) do |pipe|
while line = pipe.gets
output << line
end
end
end
rescue TimeoutError
end

puts output

4

Ahmad A. wrote:

puts ‘execution expired’
end

This might do the job

I don’t think you will get a value in status that way. Try this:

require ‘timeout’

output = []
begin
Timeout.timeout 5 do
IO.popen(“ping 192.168.1.1”) do |pipe|
while line = pipe.gets
output << line
end
end
end
rescue TimeoutError
end

puts output

5

Joel VanderWerf wrote:

I don’t think you will get a value in status that way. Try this:

require ‘timeout’

output = []
begin
Timeout.timeout 5 do
IO.popen(“ping 192.168.1.1”) do |pipe|
while line = pipe.gets
output << line
end
end
end
rescue TimeoutError
end

puts output

Thanks for the correction. Actually I’m running javascript interpreter
program called spidermonkey and it does not require storing values.
After finished it will generate a file. However sometimes if the
javascript code is not properly coded, or with infinite loops, the
javascript interpreter will just hang in there waiting. So I dont want
that to happen. Need to get it stop if it tooks more than 10 seconds.

I’ve tried using the timeout, and it worked. However, I’ve found out
that the program’s process still running in background, which in this
case it did not terminate after the timeout. How can I stop the process
after reaching the timeout?