What permissions are needed to write a PID file in /var/run?

Solution 1:

By default, you can only write to /var/run as a user with an effective user ID of 0 (ie as root). This is for good reasons, so whatever you do, don't go and change the permissions of /var/run... Instead, as root, create a directory under /var/run:

# mkdir /var/run/mydaemon

Then change its ownership to the user/group under which you wish to run your process:

# chown myuser:myuser /var/run/mydaemon

Now specify to use /var/run/mydaemon rather than /var/run.

You can always test this by running a test as the user in question.

Solution 2:

mkdir /var/run/mydaemon
chown myuser:myuser /var/run/mydaemon

this will not work, since it will be lost at the next reboot (/var/run is a tmpfs on Ubuntu).

The only feasible solution is to run mkdir and chmod as part of the startup scripts.

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Solution 3:

You can try this. Create a directory /var/run/test/ and then change the permission of this directory to the same user as your program runs. " chown /var/run/test/" . Now in your application change the location of the PID file to /var/run/test/test.pid. This should get things working for you.

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Solution 4:

What about using the "sticky" bit on /var/run ?

chmod +t /var/run ?

Probably mess up some other apps, but it seems like it would be another solution.

I'll stick with creating a separate /var/run folder for now, however.