I need to check for dpkg lock before installing apps in a script

Question

I have a problem with a script I wrote to install a bunch of apps, basically as it loops through an array of app names to install it checks them by doing:

dpkg -l | grep -q $i

and based on the $? will either install or skip the app. Trouble is for a few items it fails due to a dpkg lock, almost the whole list works, just half a dozen fail but work if you run the script again.

Is it possible to wait for dpkg to finish before running the 'apt-get install'?

For now I've added a 'sleep 0.5' between the 2 lines and this has stopped the problem but is obviously ugly and slower.

Thanks, Noki

How do I use this in a non-interactive script. This appears to need user input each time it queues up an application to install? — Noki, May 17 '14 at 15:46

score 12 · Accepted Answer · answered May 17 '14 at 14:16

12

To identify processes using files or sockets you can use fuser command (see man fuser for more info). In case of dpkg, you can check for the lock as root with the following command:

fuser /var/lib/dpkg/lock

answered May 17 '14 at 14:16

Radu Rădeanu

169,590

4

Your answer on this question is much better/helpful IMO. – jobin May 17 '14 at 14:18
1

@Jobin This answer only to the current question. – Radu Rădeanu May 17 '14 at 14:47

I need to check for dpkg lock before installing apps in a script

1 Answers1