IBWRT(3)

✨ IBWRT(3) ✨

okay bestie, welcome to the Traditional API Functions chapter of the manual, and today's main character is ibwrt 💅

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🌸 NAME 🌸

ibwrt — write data bytes (board or device) 🦋

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✨ SYNOPSIS ✨

#include <gpib/ib.h>

int ibwrt(int ud, const void *data, long num_bytes);

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💖 DESCRIPTION 💖

so like, ibwrt() is literally the function you call to write data bytes to a device or a board 🎀 The ud argument can be either a device or a board descriptor</> — yes, she's flexible like that, we love a versatile queen 👑

num_bytes tells her exactly how many bytes to write out of the user-supplied array data. no guessing, no vibes-based counting, you tell her the number and she sends the number, periodt ✋

EOI may be asserted with the last byte sent, or when the end-of-string character is sent (see ibeos() and ibeot() for the deets, iykyk 🫶).

now, the write operation may be interrupted by:

• a timeout (see ibtmo()) ⏰
• the board receiving a device clear command 💀
• or receiving an interface clear 😭

like she can get cut off mid-sentence, it's giving group-chat message that never sent 🙈

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🧚 how it behaves — device descriptor edition 🧚

If ud is a device descriptor, then the library automatically handles addressing the device as listener</> and the interface board as talker</>, before sending the data bytes onto the bus. she does the whole addressing choreography for you behind the scenes, no cap, you just show up with your bytes 🌈

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👑 how it behaves — board descriptor edition 👑

If ud is a board descriptor, then the board simply writes the data onto the bus. and here's the plot twist — the controller-in-charge must address the board as talker. that part is on you, bestie, she is not doing it for you this time 💅

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🍓 the post-call tea 🍓

After the ibwrt() call, ibcnt and ibcntl are set to the number of bytes written 📝 so you can check how much actually made it out there. receipts, basically 🧾✨

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⭐ RETURN VALUE ⭐

The value of ibsta is returned. that's it, that's the whole return value, she keeps it iconic 💜

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🎀 COPYRIGHT 🎀

Copyright © 2003-2006, 2008 Frank Mori Hess

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ngl the whole thing is giving "trust the library, she handles the addressing" energy, and honestly? she ate 🔥

linux-gpib 4.3.7 · 07/06/2026 — that's the version and the date of this lil masterpiece, so if you're quoting her, cite her properly bestie 😌🫶 bye now, go write some bytes! 🌟