IBWRTA(3)

💫 IBWRTA(3) — Traditional API Functions 💫

okay bestie, pull up a chair, because we're about to talk about ibwrta — the async queen of the Traditional API Functions section 👑 this one's from the linux-gpib girlies and she does NOT wait around for anyone, fr fr.

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✨ NAME ✨

ibwrta — write data bytes asynchronously (board or device) 💅

like. it writes. it does it async. that's the whole vibe.

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✨ SYNOPSIS ✨

#include <gpib/ib.h>

int ibwrta(int ud, const void *buffer, long num_bytes);

look at her. three little params. so clean. so iconic. 🎀

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✨ DESCRIPTION ✨

so here's the tea ☕ — ibwrta() is basically ibwrt() but with main character energy. same idea, except it operates asynchronously. and the way that means it does not sit there waiting for the sending of the data bytes to complete? it just returns immediately. boom. done. bye. 🦋

⚠️ okay but this is the important part, no cap: while an asynchronous operation is in progress, most library functions will fail with an EOIP error. so don't be out here calling random stuff mid-write and then acting surprised, bestie, you were warned 💀

so how do you actually successfully complete an asynchronous operation? you gotta call ibwait() with CMPL set in the wait mask, and you keep doing that until the CMPL bit is set in ibsta. that's the resync ritual. don't skip it. 🕯️✨

and if you're like "actually no, I changed my mind, abort mission"? totally valid. asynchronous operations may also be aborted with an ibstop() or ibonl() call. slay, you have options. 🙈

now — after the asynchronous I/O has completed and the results have been resynchronized with the current thread, there are these Linux-GPIB extensions that are lowkey super useful: AsyncIbsta, AsyncIberr, AsyncIbcnt, and AsyncIbcntl. why do we love them? because they let you more cleanly separate the results of the asynchronous I/O from the results of the ibwait() or similar call you used to resynchronize. it's giving organized. it's giving unbothered. it's giving clean data hygiene. 🧚💖

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✨ RETURN VALUE ✨

the value of ibsta is returned. that's it, that's the return. periodt. 💅

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✨ COPYRIGHT ✨

Copyright © 2003-2006, 2008 Frank Mori Hess

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and that's the page, gorgeous 🫶 shoutout to linux-gpib 4.3.7, dated 07/06/2026 — go forth and write your bytes asynchronously, and remember: CMPL in the wait mask or it didn't happen 💜🌸⭐