Scroll to navigation

COMEDI_GET_BUFFER_WR(3) Comedi reference COMEDI_GET_BUFFER_WR(3)

NAME

comedi_get_buffer_write_offset - streaming buffer write offset

SYNOPSIS

#include <comedilib.h>

int comedi_get_buffer_write_offset(comedi_t * device, unsigned int subdevice);

DESCRIPTION

The function comedi_get_buffer_write_offset is used on a subdevice that has a Comedi command in progress to get the current write position in the streaming buffer as an offset in bytes from the start of the buffer. The position will wrap around to 0 when it reaches the buffer size. This offset is only useful for memory mapped buffers.

RETURN VALUE

On success, comedi_get_buffer_write_offset returns the current write position as an offset in bytes from the start of the buffer. On failure, -1 is returned.

AUTHORS

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.

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.

12/30/2018 Comedi