comedi_loglevel - change Comedilib logging properties

DavidSchleef <ds@schleef.org>
           Author.

       FrankMoriHess <fmhess@users.sourceforge.net>
           Author.

       HermanBruyninckx <Herman.Bruyninckx@mech.kuleuven.ac.be>
           Author.

       BerndPorr <tech@linux-usb-daq.co.uk>
           Author.

       IanAbbott <abbotti@mev.co.uk>
           Author.

       ÉricPiel <piel@delmic.com>
           Author.

       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.

Comedi                                             08/06/2025                                 COMEDI_LOGLEVEL(3)

       This function affects the output of debugging and error messages from Comedilib. By increasing the log
       level loglevel, additional debugging information will be printed. Error and debugging messages are
       printed to the standard error output stream stderr.

       The default loglevel can be set by using the environment variable COMEDI_LOGLEVEL. The default log level
       is 1.

       In order to conserve resources, some debugging information is disabled by default when Comedilib is
       compiled.

       The meaning of the log levels is as follows:
       ┌──────────┬───────────────────────────────────┐
       │ Loglevel │ Behavior                          │
       ├──────────┼───────────────────────────────────┤
       │ 0        │ Comedilib prints nothing.         │
       ├──────────┼───────────────────────────────────┤
       │ 1        │ (default) Comedilib prints error  │
       │          │ messages when                     │
       │          │      there is a self-consistency  │
       │          │ error (i.e., an internal bug.)    │
       ├──────────┼───────────────────────────────────┤
       │ 2        │ Comedilib prints an error message │
       │          │ when an invalid                   │
       │          │      parameter is passed.         │
       ├──────────┼───────────────────────────────────┤
       │ 3        │ Comedilib prints an error message │
       │          │ whenever an                       │
       │          │      error is generated in the    │
       │          │ Comedilib library or in the C     │
       │          │ library,                          │
       │          │      when called by Comedilib.    │
       ├──────────┼───────────────────────────────────┤
       │ 4        │ Comedilib prints a lot of junk.   │
       └──────────┴───────────────────────────────────┘

       comedi_loglevel - change Comedilib logging properties

       This function returns the previous log level.

#include<comedilib.h>intcomedi_loglevel(intloglevel);