I prefer daemontools for background processes, as explained in Re: keep a module in shared memory. No need to add a single line of code to your script, no race conditions when handling PID files (because daemontools do not need PID files), and a simple control mechanism. Just write a char to a pipe or let the svc utility do that for you.

(And yes, djb's behaviour regarding errno is just silly and childish. Apply the patch from thedjbway.org or complain loudly to djb that he does not want to accept the C standards. And by the way, also apply the other patch that adds support for SIGQUIT, SIGUSR1, and SIGUSR2.)

Alexander