COMEDI_OPEN(3)

✨ COMEDI_OPEN(3) ✨

okay bestie, welcome to the Comedi reference manual, the comedi_open page 💖 this is the one that gets you into a Comedi device, like the velvet rope moment of your whole DAQ journey 🎀

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🌸 NAME 🌸

comedi_open — open a Comedi device 🦋

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💅 SYNOPSIS 💅

#include <comedilib.h>

comedi_t * comedi_open(const char * filename);

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🫶 DESCRIPTION 🫶

So basically, comedi_open opens up a Comedi device, and you tell it which one you want with the filename file. That's it, that's the whole vibe ✨

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👑 RETURN VALUE 👑

If everything goes slay, comedi_open hands you back a pointer to a totally valid comedi_t structure. But listen — this structure is opaque, meaning you do not dereference that pointer in your application. Not even a little. Not even to peek. 🙈

If it fails? You get NULL. That's your sign, bestie 😭 go check yourself.

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🧚 AUTHORS 🧚

These are the icons who made it 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 🌈

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.

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.

fr fr, read the license, it's giving important and it's not optional 💀

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aaaand that's the page, bestie 🎀 this came out of the Comedi manual, dated 03/20/2026, and it lives under the COMEDI_OPEN(3) name 💖 go open some devices, you got this ⭐👑