io_eagain(3)

✨ io_eagain(3) — Library Functions Manual ✨

okay bestie, gather round 🫶 this is a lil page from the Library Functions Manual, and it's about one very specific, very niche, but very important job: telling io_wait that you got an EAGAIN. that's it. that's the whole thing. and yet 💅

🌸 NAME 🌸

io_eagain — tell io_wait that you got an EAGAIN

like, literally just snitching to io_wait that the read didn't go through this time 🍓

🎀 SYNTAX 🎀

#include <libowfat/io.h>

void io_eagain(int64 fd);

yep, that's the whole signature. one int64 fd, zero return value, all vibes ✨

🦋 DESCRIPTION 🦋

okay so picture this: io_wait() told you that you can read from a descriptor 👑 so you go to read from it, all confident, main character energy, and then… EAGAIN. 😭 the read said "not right now babe."

when that happens, you need to tell io_wait(). fr fr, this is not optional. it's important for edge triggered event notification schemes — think Linux 2.4's SIGIO — because if you don't tell it, you will lose events. like, gone. no cap. 💀

the good news? io_tryread(), io_trywrite(), io_sendfile() and iob_send() already take care of this for you 🫶 they handle the EAGAIN situation internally so you never have to think about it. iconic behaviour honestly.

so when do you actually care about this function? only if you're integrating io_wait() with legacy code that uses read/write directly. that's the one scenario. iykyk 🧚

💖 SEE ALSO 💖

• io_wait(3)

and that's the tea, bestie 🌈 this was io_eagain(3), from the Library Functions Manual — go forth, tell io_wait about your EAGAINs, and don't lose those events. periodt. 💅✨🎀