ibm-information-center/dist/eclipse/plugins/i5OS.ic.apis_5.4.0.1/linku.htm

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<title>QlgLink()--Create Link to File (using NLS-enabled path name)</title>
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<h2>QlgLink()--Create Link to File (using NLS-enabled path name)</h2>
<div class="box" style="width: 80%;">
<br>
&nbsp;&nbsp;Syntax<br>
<pre>
#include &lt;unistd.h&gt;
int QlgLink(Qlg_Path_Name_T <em>*existing</em>, Qlg_Path_Name_T <em>*new</em>);
</pre>
&nbsp;&nbsp;Service Program Name: QP0LLIB1<br>
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<br>
&nbsp;&nbsp;Default Public Authority: *USE<br>
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<br>
&nbsp;&nbsp;Threadsafe: Conditional; see Usage Notes for <a
href="link.htm">link()</a>.<br>
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<br>
</div>
<p>The <strong>QlgLink()</strong> function, like the <strong>link()</strong>
function, provides an alternative path name for the existing file so that the
file can be accessed by either the existing name or the new name. The
difference is that the <strong>QlgLink()</strong> function supports pointers to
Qlg_Path_Name_T structures, while <strong>link()</strong> supports pointers to
character strings.</p>
<p>Limited information on the <em>existing</em> and the <em>new</em> parameters
is provided here. For more information on these parameters and for a discussion
of the authorities required, return values, and related information, see <a
href="link.htm">link()</a>--Create Link to File.</p>
<br>
<h3>Parameters</h3>
<dl>
<dt><strong><em>existing</em></strong></dt>
<dd>(Input) A pointer to a Qlg_Path_Name_T structure that contains a path name
or a pointer to a path name of an existing file to which a new link is to be
created. For more information on the Qlg_Path_Name_T structure, see <a href=
"../apiref/pns.htm">Path name format</a>.<br>
<br>
</dd>
<dt><strong><em>new</em></strong></dt>
<dd>(Input) A pointer to a Qlg_Path_Name_T structure that contains a path name
or a pointer to a path name that is the name of the new link. For more
information on the Qlg_Path_Name_T structure, see <a href="../apiref/pns.htm">Path name
format</a>.</dd>
</dl>
<br>
<h3>Related Information</h3>
<ul>
<li><a href="link.htm">link()</a>--Create Link to File<br>
<br>
</li>
<li><a href="qp0lunlk.htm">Qp0lUnlink()</a>--Remove Link to File (using
NLS-enabled path name)</li>
</ul>
<br>
<h3>Example</h3>
<p>See <a href="../apiref/aboutapis.htm#codedisclaimer">Code disclaimer information</a>
for information pertaining to code examples.</p>
<p>The following example uses <strong>QlgLink()</strong>:</p>
<pre>
#include &lt;stdio.h&gt;
#include &lt;unistd.h&gt;
#include &lt;sys/types.h&gt;
#include &lt;sys/stat.h&gt;
#include &lt;fcntl.h&gt;
#include &lt;stdlib.h&gt;
#include &lt;Qp0lstdi.h&gt;
main()
{
int file_descriptor;
struct stat info;
#define mypath_fn "link.example.file"
#define mypath_ln "link.example.link"
const char US_const[3]= "US";
const char Language_const[4] ="ENU";
typedef struct pnstruct
{
Qlg_Path_Name_T qlg_struct;
char pn[100]; /* This array size must be &gt;= the */
/* length of the path name or must */
/* be a pointer to the path name. */
};
struct pnstruct path_fn;
struct pnstruct path_ln;
/***************************************************************/
/* Initialize Qlg_Path_Name_T parameters */
/***************************************************************/
memset((void*)&amp;path_fn, 0x00, sizeof(struct pnstruct));
path_fn.qlg_struct.CCSID = 37;
memcpy(path_fn.qlg_struct.Country_ID,US_const,2);
memcpy(path_fn.qlg_struct.Language_ID,Language_const,3);
path_fn.qlg_struct.Path_Type = QLG_CHAR_SINGLE;
path_fn.qlg_struct.Path_Length = sizeof(mypath_fn)-1;
path_fn.qlg_struct.Path_Name_Delimiter[0] = '/';
memcpy(path_fn.pn,mypath_fn,sizeof(mypath_fn)-1);
memset((void*)&amp;path_ln, 0x00, sizeof(struct pnstruct));
path_ln.qlg_struct.CCSID = 37;
memcpy(path_ln.qlg_struct.Country_ID,US_const,2);
memcpy(path_ln.qlg_struct.Language_ID,Language_const,3);
path_ln.qlg_struct.Path_Type = QLG_CHAR_SINGLE;
path_ln.qlg_struct.Path_Length = sizeof(mypath_ln)-1;
path_ln.qlg_struct.Path_Name_Delimiter[0] = '/';
memcpy(path_ln.pn,mypath_ln,sizeof(mypath_ln)-1);
if ((file_descriptor = QlgCreat((Qlg_Path_Name_T *)&amp;path_fn, S_IWUSR)) &lt; 0)
perror("QlgCreat() error");
else {
close(file_descriptor);
puts("before QlgLink()");
QlgStat((Qlg_Path_Name_T *)&amp;path_fn,&amp;info);
printf(" number of links is %hu\n",info.st_nlink);
if (QlgLink((Qlg_Path_Name_T *)&amp;path_fn,
(Qlg_Path_Name_T *)&amp;path_ln) != 0) {
perror("QlgLink() error");
QlgUnlink((Qlg_Path_Name_T *)&amp;path_fn);
}
else {
puts("after QlgLink()");
QlgStat((Qlg_Path_Name_T *)&amp;path_fn,&amp;info);
printf(" number of links is %hu\n",info.st_nlink);
QlgUnlink((Qlg_Path_Name_T *)&amp;path_ln);
puts("after first QlgUnlink()");
QlgLstat((Qlg_Path_Name_T *)&amp;path_fn,&amp;info);
printf(" number of links is %hu\n",info.st_nlink);
QlgUnlink((Qlg_Path_Name_T *)&amp;path_fn);
}
}
}
</pre>
<p><strong>Output:</strong></p>
<pre>
before QlgLink()
number of links is 1
after QlgLink()
number of links is 2
after first QlgUnlink()
number of links is 1
</pre>
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API introduced: V5R1
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