Yep, fd should be the file descriptor, but for lazyness when manually calling the function sometimes we supply 0 as fd and event. Instead of fixing the usage, do as other of such functions do in this circumstances: use c->fd.

otherwise clients will remain stuck waiting for a pending request that doesn't exist (see apply_fastcgi switch.)

it's not technically required, since a couple of lines below we free whole host struct, and we don't have code that may use h->{env,aliases} afterwards, but it's nice not to have invalid pointers around. it may bite in the future.

man -Tlint