it's faster (statistically speaking) to first compute if the option is set and then fnmatch than the inverse. This way we can avoid unnecessary fnmatch.

it's a waste to loop through all fds. We know the *exact* number of clients that needs attention, so use that information to limit the looping.

keep mark_nonblock in utils.c, as otherwise the build for the regress suite will fail (mark_nonblock needs fatal which is in gmid.c, and we can't link gmid.o with the regress suite...)

By marking all those function as static, the compiler is free to do more optimizations. In addition, those functions are not used outside server.c