Getting sudo and nohup to work together

Question

Linux newbie here.

I have a perl script which takes two command line inputs. I tried to run it in the background but this is what I got:

[~user]$ nohup sudo ./ascii_loader_script.pl 20070502 ctm_20070502.csv & [2] 19603 [~user]$ nohup: appending output to `nohup.out' 

after the system returns "nohup: appending output to `nohup.out'", no new prompt will appear. Then as long as I type in some other command, the shell will tell me that the process is stopped:

[~user]$ nohup sudo ./ascii_loader_script.pl 20070502 ctm_20070502.csv & [2] 19603 [~user]$ nohup: appending output to `nohup.out' ls ascii_loader_script.pl  format_wrds_trd.txt  nohup.out  norm_wrds_trd.cfg [2]+  Stopped                 nohup sudo ./ascii_loader_script.pl 20070502 ctm_20070502.csv 

I've looked at this post and tried to do "sudo date" before executing the command. Still got the same thing. http://www.sudo.ws/pipermail/sudo-users/2003-July/001648.html

Answer 1

The solution is to use the -b flag for sudo to run the command in the background:

$ sudo -b ./ascii_loader_script.pl 20070502 ctm_20070502.csv 

You should only use nohup if you want the program to continue even after you close your current terminal session

Answer 2

The problem here, imho, is not nohup, but background processing sudo.

You are putting the process in background (& at end of command) but probably sudo needs password authentication, and that is why the process stops.

Try one of these:

1) remove the ampersand from end of command, reply to passord prompt and afterwords put it in background (by typing CTRL-Z - which stops the process and issuing the bg command to send it to background)

2) Change the /etc/sudoers to not ask for users password by including the line: myusername ALL=(ALL) NOPASSWD: ALL

If besides the password reply your application waits for other input, then you can pipe the input to the command like this: $ cat responses.txt|sudo mycommand.php

hth