[En-Nut-Discussion] Let's start another discussion: Wait on multiple events

[Ole Reinhardt]

Hi all,

lets's start another interesting discussion.

Since long time I'm thinking about writing da select or poll function
for NutOS.

For those who don't know what these functions are used for: Other
operating systems provide those two functions to wait on several file
descriptors becomming ready to read / write.

I just tried to understand how linux select is working internaly, but
suffered a bit from the complexity of this implementation.

The linux implementation seem to use several wait queues. One for every
device driver. A device driver now signals this queue and therefor wakes
up the calling application. The point where I'm los now: The select
system call needs to wait on multiple waitqueues at the same time?

Does anyone know more about the internal implementation of select and
poll? Is there a possibility to "emulate" select with the existing NutOs
event queues?

Any suggestions or literature on this subject?

Regards,

Ole Reinhardt

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