Is it safe to create a link to a socket file in /tmp?

Question

I'm a bit confused as to see that going from one Linux distribution to another, the package managers will sometimes configure processes to create the socket file either in /tmp or in /var/run/%process%, but I'm seeing it as a standard in open source projects that you configure your applications to refer to the socket in /tmp, as if to normalize the two options.

I too have chosen to distribute a project's configuration to refer to the socket in /tmp. Now I'd like to know, for the sake of not overriding the defaults, if I'd like to link a socket from /var/run into /tmp, is there a safe way to do that?

I'm mostly asking this because I wouldn't like somebody to deal with spurious application errors because the /tmp directory got wiped clean and the socket link is no longer there.

Answer 1

/tmp is not a "standard"⁰ anymore for system daemons; the only program in wide use¹ that still puts sockets there is Xorg. All other daemons use /run or /var/run for this – precisely to avoid such problems as periodic /tmp cleaning or possible name collisions with user-created sockets.

There is no standard method of cleaning /tmp or excluding files from said cleanup.

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⁰ The FHS has never defined /tmp for anything else but temporary files.

¹ That I know of.