'\" t
.\"     Title: comedi_set_buffer_size
.\"    Author: David Schleef <ds@schleef.org>
.\" Generator: DocBook XSL Stylesheets v1.79.1 <http://docbook.sf.net/>
.\"      Date: 12/30/2018
.\"    Manual: Comedi reference
.\"    Source: Comedi
.\"  Language: English
.\"
.TH "COMEDI_SET_BUFFER_SI" "3" "12/30/2018" "Comedi" "Comedi reference"
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.SH "NAME"
comedi_set_buffer_size \- streaming buffer size of subdevice
.SH "SYNOPSIS"
.sp
.ft B
.nf
#include <comedilib\&.h>
.fi
.ft
.HP \w'int\ comedi_set_buffer_size('u
.BI "int comedi_set_buffer_size(comedi_t\ *\ " "device" ", unsigned\ int\ " "subdevice" ", unsigned\ int\ " "size" ");"
.SH "DESCRIPTION"
.PP
The function
\fBcomedi_set_buffer_size\fR
changes the size of the streaming buffer for the subdevice specified by
\fIdevice\fR
and
\fIsubdevice\fR\&. The buffer size will be set to
\fIsize\fR
bytes, rounded up to a multiple of the virtual memory page size\&. The virtual memory page size can be determined using
sysconf(_SC_PAGE_SIZE)\&.
.PP
This function does not require special privileges\&. However, it is limited to a (adjustable) maximum buffer size, which can be changed by a privileged user calling
\fBcomedi_set_max_buffer_size\fR, or running the program
\fBcomedi_config\fR\&.
.SH "RETURN VALUE"
.PP
On success,
\fBcomedi_set_buffer_size\fR
returns the new buffer size in bytes\&. On failure,
\-1
is returned\&.
.PP
.SH "AUTHORS"
.PP
\fBDavid Schleef\fR <\&ds@schleef.org\&>
.RS 4
Author.
.RE
.PP
\fBFrank Mori Hess\fR <\&fmhess@users.sourceforge.net\&>
.RS 4
Author.
.RE
.PP
\fBHerman Bruyninckx\fR <\&Herman.Bruyninckx@mech.kuleuven.ac.be\&>
.RS 4
Author.
.RE
.PP
\fBBernd Porr\fR <\&tech@linux-usb-daq.co.uk\&>
.RS 4
Author.
.RE
.PP
\fBIan Abbott\fR <\&abbotti@mev.co.uk\&>
.RS 4
Author.
.RE
.PP
\fB\('Eric Piel\fR <\&piel@delmic.com\&>
.RS 4
Author.
.RE
.SH "COPYRIGHT"
.br
Copyright \(co 1998-2003 David Schleef
.br
Copyright \(co 2001-2003, 2005, 2008 Frank Mori Hess
.br
Copyright \(co 2002-2003 Herman Bruyninckx
.br
Copyright \(co 2012 Bernd Porr
.br
Copyright \(co 2012 Ian Abbott
.br
Copyright \(co 2012, 2015 \('Eric Piel
.br
.PP
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.
.PP
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.
.PP
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.
.PP
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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