[nitwit005]

If you don't think pipes offer much, don't use them.

Saying "long function call" doesn't mean much since a function can take infinitely long.

[marcosdumay]

A long distance function call, that invalidates everything on your cache.

[saagarjha]

…which is quite expensive.

[marcosdumay]

Yes, it is. But it's much cheaper than interacting by pipe.

Linux is optimizing sockets with a similar goal. And it's quite far on that direction. But there's still some margin to gain.