Shell exit code


#1

Hello Group,

Is there any way to retrieve an exit code of shell commands when called
from ruby?

ruby code :

exec(“ls”) if fork.nil?
Process.wait

shell :

ls

echo $? <-- get this value in ruby


#2

shell :

ls

echo $? <-- get this value in ruby

As of Ruby 1.9, you indeed have the $? global variable, which references
the
exit status of the last child process to terminate. In your example,
exec
will replace the subprocess by running the given command, thus $? will
contain its exit status.

irb(main):001:0> exec(‘ls’) if fork.nil?; Process.wait; puts $?
tmp
pid 5552 exit 0

irb(main):002:0> exec(‘cat /etc/sudoers’) if fork.nil?; Process.wait;
puts
$?
cat: /etc/sudoers: Permission denied
pid 5556 exit 1

Hope it helps
Cheers

Alex


#3

Hello Alex,

Thank you for your advise. This really helped!

Regards,
Yuguri

Alex Eiras wrote:

shell :

ls

echo $? <-- get this value in ruby

As of Ruby 1.9, you indeed have the $? global variable, which references
the
exit status of the last child process to terminate. In your example,
exec
will replace the subprocess by running the given command, thus $? will
contain its exit status.

irb(main):001:0> exec(‘ls’) if fork.nil?; Process.wait; puts $?
tmp
pid 5552 exit 0

irb(main):002:0> exec(‘cat /etc/sudoers’) if fork.nil?; Process.wait;
puts
$?
cat: /etc/sudoers: Permission denied
pid 5556 exit 1

Hope it helps
Cheers

Alex