1COMEDI_GET_BUFFER_WR(3) Comedi reference COMEDI_GET_BUFFER_WR(3)
2
3
4
6 comedi_get_buffer_write_offset - streaming buffer write offset
7
9 #include <comedilib.h>
10
11 int comedi_get_buffer_write_offset(comedi_t * device,
12 unsigned int subdevice);
13
15 The function comedi_get_buffer_write_offset is used on a subdevice that
16 has a Comedi command in progress to get the current write position in
17 the streaming buffer as an offset in bytes from the start of the
18 buffer. The position will wrap around to 0 when it reaches the buffer
19 size. This offset is only useful for memory mapped buffers.
20
22 On success, comedi_get_buffer_write_offset returns the current write
23 position as an offset in bytes from the start of the buffer. On
24 failure, -1 is returned.
25
27 David Schleef <ds@schleef.org>
28 Author.
29
30 Frank Mori Hess <fmhess@users.sourceforge.net>
31 Author.
32
33 Herman Bruyninckx <Herman.Bruyninckx@mech.kuleuven.ac.be>
34 Author.
35
36 Bernd Porr <tech@linux-usb-daq.co.uk>
37 Author.
38
39 Ian Abbott <abbotti@mev.co.uk>
40 Author.
41
42 Éric Piel <piel@delmic.com>
43 Author.
44
46 Copyright © 1998-2003 David Schleef
47 Copyright © 2001-2003, 2005, 2008 Frank Mori Hess
48 Copyright © 2002-2003 Herman Bruyninckx
49 Copyright © 2012 Bernd Porr
50 Copyright © 2012 Ian Abbott
51 Copyright © 2012, 2015 Éric Piel
52
53 This document is part of Comedilib. In the context of this document,
54 the term "source code" as defined by the license is interpreted as the
55 XML source.
56
57 This library is free software; you can redistribute it and/or modify it
58 under the terms of the GNU Lesser General Public License as published
59 by the Free Software Foundation, version 2.1 of the License.
60
61 This library is distributed in the hope that it will be useful, but
62 WITHOUT ANY WARRANTY; without even the implied warranty of
63 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser
64 General Public License for more details.
65
66 You should have received a copy of the GNU Lesser General Public
67 License along with this library; if not, write to the Free Software
68 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
69 USA.
70
71
72
73
74Comedi 05/11/2017 COMEDI_GET_BUFFER_WR(3)