Created attachment 130930 [details] [review]
My suggestion

This is my proposed patch to enhance it.

One thing I thought about is when the user presses ctrl-c when an EOS is already at the pipeline. What happens when we try to push another one? Is that possible?

At a glance it looks good.

I think you should store the state of what's been going on.

If --eos-on-shutdown and CTRL-C => send EOS => mark state as having sent EOS
If you press CTRL-C again => see that we've already sent EOS => Do the normal shutdown (current behaviour).

Small nitpick and two suggestions:

 - would be nice if you turned the defines into an enum type
   (EventLoopResult or something similar)

 - another PRINT "Waiting for ..." after the send_event()
   would be good, I think

 - how about another PRINT after the last event_loop run to
   tell the user either that we got an EOS message and all
   is well, or something else happened and we didn't shut
   down cleanly?
 

Created attachment 131036 [details] [review]
Updated patch

Updated with the suggestions

Created attachment 131064 [details] [review]
Updated patch

Looks nice. Two comments:

typedef enum _EventLoopResult
{
  NO_ERROR = 0,
  ERROR,
  INTERRUPT
} EventLoopResult;

I wonder how hight the chances are that this clashes with some defines. What about

typedef enum _EventLoopResult
{
  ELR_NO_ERROR = 0,
  ELR_ERROR,
  ELR_INTERRUPT
} EventLoopResult;

also in main, just spell out the variable.
eos_on_shutd -> eos_on_shutdown

Created attachment 131442 [details] [review]
Updated patch

Committed.

git commit hash:
5fa36d9f3d8d2fddc5171de927f0640f5ef056b4