sock_upcall vs select for kernel socket polling?

Question

alkap OP

Created Aug ’24

Replies 2

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I've been using sock_upcall to do socket polling in my VFS kext.

Perusing the Darwin/XNU sources, I've stumbled upon select.

Which is the recommended way to do socket polling in the kernel, sock_upcall or select?

Thanks.

Answered by DTS Engineer in 801627022

select is a user-space thing; you can’t use it within the kernel.

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Answer 1

DTS Engineer OP

Apple

Aug ’24

Accepted Answer

Recommended

select is a user-space thing; you can’t use it within the kernel.

Share and Enjoy
—
Quinn “The Eskimo!” @ Developer Technical Support @ Apple
let myEmail = "eskimo" + "1" + "@" + "apple.com"

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Answer 2

alkap OP

Aug ’24

Thanks for replying.

I had a closer look at the signature of select and realised that there was no way I knew of that I could get a file descriptor to pass into it within the kernel.

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