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<title>QlgSem_open_np()--Open Named Semaphore with Maximum Value (using
NLS-enabled path name)</title>
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<h2>QlgSem_open_np()--Open Named Semaphore with Maximum Value (using
NLS-enabled path name)</h2>
<div class="box" style="width: 80%;">
<br>
&nbsp;&nbsp;Syntax
<pre>
#include &lt;semaphore.h&gt;
#include &lt;qlg.h&gt;
sem_t * QlgSem_open_np(const Qlg_Path_Name_T *<em>name</em>, int <em>oflag</em>
mode_t <em>mode</em>, unsigned int <em>value</em>,
sem_attr_np_t * <em>attr</em>);
</pre>
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&nbsp;&nbsp;Service Program Name: QP0ZPSEM<br>
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&nbsp;&nbsp;Threadsafe: Yes<br>
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<p>The <strong>QlgSem_open_np()</strong> function, like the <strong>
sem_open_np()</strong> function, opens a named semaphore and returns a
semaphore pointer that may be used on subsequent calls to <strong>
sem_post()</strong>, <strong>sem_post_np()</strong>, <strong>
sem_wait()</strong>, <strong>sem_wait_np()</strong>, <strong>
sem_trywait()</strong>, <strong>sem_getvalue()</strong>, and <strong>
sem_close()</strong>. The <strong>QlgSem_open_np()</strong> function takes a
pointer to a Qlg_Path_Name_T structure, while the <strong>
sem_open_np()</strong> function takes a pointer to a character string.</p>
<p>Limited information on the <em>name</em> parameter is provided in this API.
For additional information on the <em>name</em> parameter and a discussion of
other parameters, authorities required, return values, and related information,
see <a href="ipcsemon.htm">sem_open_np()</a>--Open Named Semaphore with Maximum
Value.</p>
<br>
<h3>Parameters</h3>
<dl>
<dt><strong>name</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 the semaphore to be opened. For more information
on the Qlg_Path_Name_T structure, see <a href="../apiref/pns.htm">Path name
format</a>.</dd>
</dl>
<br>
<h3>Error Conditions</h3>
<p>If <strong>QlgSem_open_np()</strong> is not successful, <em>errno</em>
usually indicates the following error or one of the errors identified in <a
href="ipcsemon.htm#ecsemon">sem_open_np()</a>--Open Named Semaphore with
Maximum Value.</p>
<dl>
<dt><em>[ECONVERT]</em></dt>
<dd>A conversion error for the parameter <em>name</em>.</dd>
</dl>
<br>
<h3>Related Information</h3>
<ul>
<li>The &lt;<strong>qlg.h</strong>&gt; file (see <a href="unix13.htm">Header
Files for UNIX-Type Functions</a>)<br>
<br>
</li>
<li><a href="ipcsemon.htm">sem_open_np()</a>--Open Named Semaphore with Maximum
Value<br>
<br>
</li>
<li><a href="ipcsemou.htm">QlgSem_open()</a>--Open Named Semaphore (using
NLS-enabled path name)<br>
<br>
</li>
<li><a href="ipcsemunu.htm">QlgSem_unlink()</a>--Unlink Named Semaphore (using
NLS-enabled path name)<br>
<br>
</li>
</ul>
<p><strong>Note:</strong> All of the related information for <strong>
sem_open_np()</strong> applies to <strong>QlgSem_open_np()</strong>. See
Related Information in <a href="ipcsemon.htm#risemon">sem_open()</a>.</p>
<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 opens the named semaphore "/mysemaphore" and creates
the semaphore with an initial value of 10 and a maxiumum value of 11. The
permissions are set such that only the current user has access to the
semaphore.</p>
<pre>
#include &lt;semaphore.h&gt;
#include &lt;qlg.h&gt;
main() {
sem_t * my_semaphore;
int rc;
sem_attr_np_t attr;
#define mypath "/mysemaphore"
const char US_const[3]= "US";
const char Language_const[4]="ENU";
const char Path_Name_Del_const[2]= "/";
typedef struct pnstruct
{
Qlg_Path_Name_T qlg_struct;
char[100] pn; /* This size must be &gt;= the path */
/* name length or be a pointer */
/* to the path name. */
};
struct pnstruct path;
/***************************************************************/
/* Initialize Qlg_Path_Name_T parameters */
/***************************************************************/
memset((void*)path name, 0x00, sizeof(struct pnstruct));
path.qlg_struct.CCSID = 37;
memcpy(path.qlg_struct.Country_ID,US_const,2);
memcpy(path.qlg_struct.Language_ID,Language_const,3);
path.qlg_struct.Path_Type = QLG_CHAR_SINGLE;
path.qlg_struct.Path_Length = sizeof(mypath)-1;
memcpy(path.qlg_struct.Path_Name_Delimiter,Path_Name_Del_const,1);
memcpy(path.pn,mypath,sizeof(mypath));
memset(&amp;attr, 0, sizeof(attr));
attr.maxvalue=11;
my_semaphore = QlgSem_open_np((Qlg_Path_Name_T *)path name,
O_CREAT|O_EXCL,
S_IRUSR | S_IWUSR,
10,
&amp;attr);
}
</pre>
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API introduced: V5R1
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