<?xml version="1.0" encoding="UTF-8"?>
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 * ...
 *
 * Copyright (C) 2012 - 2016 - Scilab Enterprises
 *
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 * pursuant to article 5.3.4 of the CeCILL v.2.1.
 * This file was originally licensed under the terms of the CeCILL v2.1,
 * and continues to be available under such terms.
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<refentry xmlns="http://docbook.org/ns/docbook" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:svg="http://www.w3.org/2000/svg" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:db="http://docbook.org/ns/docbook" xmlns:scilab="http://www.scilab.org" xml:lang="en" xml:id="mseek">
    <refnamediv>
        <refname>mseek</refname>
        <refpurpose>sets current position in a binary file</refpurpose>
    </refnamediv>
    <refsynopsisdiv>
        <title>Syntax</title>
        <synopsis>mseek(n [,fd, flag])</synopsis>
    </refsynopsisdiv>
    <refsection>
        <title>Arguments</title>
        <variablelist>
            <varlistentry>
                <term>n</term>
                <listitem>
                    <para>a scalar: the offset in a number of bytes.</para>
                </listitem>
            </varlistentry>
            <varlistentry>
                <term>fd</term>
                <listitem>
                    <para>
                        a scalar: a file descriptor returned by the function
                        <function>mopen</function>. <literal>-1</literal>
                        stands for last opened file. Default value is
                        <literal>-1</literal>.
                    </para>
                </listitem>
            </varlistentry>
            <varlistentry>
                <term>flag</term>
                <listitem>
                    <para>
                        a string: specifies the origin. Default value <literal>'set'</literal>.
                    </para>
                </listitem>
            </varlistentry>
        </variablelist>
    </refsection>
    <refsection>
        <title>Description</title>
        <para>
            The function <function>mseek</function> sets the position of the next input or output operation on the stream <varname>fd</varname>. The new position is at the signed distance given by <varname>n</varname> bytes from the beginning, from the current position, or from the end of the file, according  to the <varname>flag</varname> value which can be <literal>'set'</literal>, <literal>'cur'</literal> or <literal>'end'</literal>. This is the reason why <varname>n</varname>  must be positive when <varname>flag</varname> is equal to <literal>'set'</literal>.
        </para>
        <para>
            <function>mseek</function> allows the file position indicator to be
            set beyond the end of the existing data in the file. If data is
            later written at this point, subsequent reads of data in the gap
            will return zero until data is actually written into the gap.
            <function>mseek</function>, by itself, does not extend the size of
            the file.
        </para>
    </refsection>
    <refsection>
        <title>Examples</title>
        <programlisting role="example"><![CDATA[
file3=fullfile(TMPDIR,'test3.bin');
fd1= mopen(file3,'wb');
for i=1:10
  mput(i,'d');
end
mseek(0);
mput(678,'d');
mseek(0,fd1,'end');
mput(932,'d');
mclose(fd1)

fd1= mopen(file3,'rb');
res=mget(11,'d')
res1=[1:11]; res1(1)=678;res1($)=932;
if res1<>res then
  write(%io(2),'Bug');
end
mseek(0,fd1,'set');

// trying to read more than stored data
res1=mget(100,'d',fd1);
if res1<>res then
  write(%io(2),'Bug');
end
meof(fd1)
mclearerr(fd1)
mclose(fd1);


file='test.bin'
file2='test2.bin'

fd1= mopen(file,'rb');
fd2= mopen(file2,'rb');

mseek(0);           // Go to the begin of the last file open (file 2). Equal to mseek(0,fd2,'set')
mseek(0,'end');     // Go to the end of the last file open (file 2). Equal to mseek(0,fd2,'end')
mseek(0,fd1);       // Go to the begin of file 1. Equal to mseek(0,fd1,'set')
mseek(2,fd1,'cur'); // Set the position to the current position offset to 2.

mclose(fd1);
mclose(fd2);

 ]]></programlisting>
    </refsection>
    <refsection role="see also">
        <title>See also</title>
        <simplelist type="inline">
            <member>
                <link linkend="mclose">mclose</link>
            </member>
            <member>
                <link linkend="meof">meof</link>
            </member>
            <member>
                <link linkend="mfprintf">mfprintf</link>
            </member>
            <member>
                <link linkend="fprintfMat">fprintfMat</link>
            </member>
            <member>
                <link linkend="mfscanf">mfscanf</link>
            </member>
            <member>
                <link linkend="fscanfMat">fscanfMat</link>
            </member>
            <member>
                <link linkend="mget">mget</link>
            </member>
            <member>
                <link linkend="mgetstr">mgetstr</link>
            </member>
            <member>
                <link linkend="mopen">mopen</link>
            </member>
            <member>
                <link linkend="mprintf">mprintf</link>
            </member>
            <member>
                <link linkend="mput">mput</link>
            </member>
            <member>
                <link linkend="mputstr">mputstr</link>
            </member>
            <member>
                <link linkend="mtell">mtell</link>
            </member>
            <member>
                <link linkend="mdelete">mdelete</link>
            </member>
        </simplelist>
    </refsection>
</refentry>
