COMEDI_DIO_READ(3)

✨ COMEDI_DIO_READ(3) ✨ — it's giving one single bit 🎀

okay bestie, sit DOWN 💅 this one lives in the Comedi reference manual, section 3 — the one where we read hardware, but make it tiny.

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🌸 NAME 🌸

comedi_dio_read — read a single bit from a digital channel 🦋

like, one (1) bit. the smallest lil guy. 🍓

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✨ SYNOPSIS ✨

#include <comedilib.h>

int comedi_dio_read(comedi_t * device, unsigned int subdevice,
                    unsigned int channel, unsigned int * bit);

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💖 DESCRIPTION 💖

ok so real talk — comedi_dio_read goes and reads the channel called channel, which belongs to the subdevice subdevice, on the device device. 🫶

the data value it pulls back gets stored in *bit. that's it, that's the whole plot. 🙈

and guess what — this function is literally equivalent to this:

comedi_data_read(device, subdevice, channel, 0, 0, bit);

no cap. same thing.

now for the plot twist that makes her so iconic: she does not require a digital subdevice, and she does not require a subdevice whose max data value is 1 — she just works anyway. 💅✨

and if you're out here wanting to read a bunch of digital channels at once? bestie, be more efficient and use comedi_dio_bitfield2 instead of calling this function over and over and over. 🔥 your CPU will thank you.

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👑 RETURN VALUE 👑

return values and errors?? same as comedi_data_read, periodt. ⭐ (so go read that one, iykyk)

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💜 AUTHORS 💜

the legends who made this happen, no cap 🌈

• David Schleef <ds@schleef.org> — Author.
• Frank Mori Hess <fmhess@users.sourceforge.net> — Author.
• Herman Bruyninckx <Herman.Bruyninckx@mech.kuleuven.ac.be> — Author.
• Bernd Porr <tech@linux-usb-daq.co.uk> — Author.
• Ian Abbott <abbotti@mev.co.uk> — Author.
• Éric Piel <piel@delmic.com> — Author.

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🎀 COPYRIGHT 🎀

the legal lore, bestie, read it carefully 💀

Copyright © 1998-2003 David Schleef
Copyright © 2001-2003, 2005, 2008 Frank Mori Hess
Copyright © 2002-2003 Herman Bruyninckx
Copyright © 2012 Bernd Porr
Copyright © 2012 Ian Abbott
Copyright © 2012, 2015 Éric Piel

this document is part of Comedilib. in the context of this document, the term "source code" as defined by the license is interpreted as the XML source. 🦋

this library is free software — you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation, version 2.1 of the License. 💚

this library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. 😭 (yes, the caps are required, that's just how licenses scream.)

you should have received a copy of the GNU Lesser General Public License along with this library; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. 📬

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ok that's the whole vibe check, bestie 🧚💖 this was Comedi, dated 03/20/2026, and you have absolutely ate this manpage. slay, go read your bits. 🌟💅