Send end-of-file through a pipe without closing the writing end?

[Zachary Santer]

This might be a little silly. If I have a process communicating to
another process in a way that involves EOF happening more than once on
one side or another of the communication, my strategy would be to do
so with a single FIFO that gets opened (and closed) for reading and
writing multiple times.

Can this instead be accomplished with an FD created by exec {fd}> >(
command ) or by the coproc keyword?

Use case currently would be some complex call to curl where it's
reading from a file for what to send in multiple http POST commands.
This file could either be a FIFO or /dev/fd/N. This is all very
conceptual right now.

Thanks,
Zack