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<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<meta name="Copyright" content="Copyright (c) 2006 by IBM Corporation">
<title>lstat()--Get File or Link Information</title>
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<h2>lstat()--Get File or Link Information</h2>
<div class="box" style="width: 70%;">
<br>
&nbsp;&nbsp;Syntax<br>
<pre>
#include &lt;sys/stat.h&gt;
int lstat(const char <em>*path</em>, struct stat <em>*buf</em>);
</pre>
&nbsp;&nbsp;Service Program Name: QP0LLIB1<br>
<!-- iddvc RMBR -->
<br>
&nbsp;&nbsp;Default Public Authority: *USE<br>
<!-- iddvc RMBR -->
<br>
&nbsp;&nbsp;Threadsafe: Conditional; see <a href="#HDRLSTAUSG">Usage Notes</a>.<br>
<!-- iddvc RMBR -->
<br>
</div>
<p>The <strong>lstat()</strong> function gets status information about a
specified file and places it in the area of memory pointed to by <em>buf</em>.
If the named file is a symbolic link, <strong>lstat()</strong> returns
information about the symbolic link itself.</p>
<p>The information is returned in the <samp>stat</samp> structure, referenced
by <em>buf</em>. For details on the <samp>stat</samp> structure, see <a href=
"stat.htm">stat()--Get File Information</a>.</p>
<p>If the named file is not a symbolic link, <strong>lstat()</strong> updates
the time-related fields before putting information in the <samp>stat</samp>
structure.</p>
<br>
<h3>Parameters</h3>
<dl>
<dt><strong><em>path</em></strong></dt>
<dd>(Input) A pointer to the null-terminated path name of the file.
<p>This parameter is assumed to be represented in the CCSID (coded character
set identifier) currently in effect for the job. If the CCSID of the job is
65535, this parameter is assumed to be represented in the default CCSID of the
job.</p>
<p>See <a href="lstatu.htm">QlgLstat()--Get File or Link Information</a> for a
description and an example of supplying the <em>path</em> in any CCSID.</p>
<br>
</dd>
<dt><strong><em>buf</em></strong></dt>
<dd>(Output) A pointer to the area to which the information should be
written.</dd>
</dl>
<br>
<h3><a name="HDRLSTAAUT">Authorities</a></h3>
<p><strong>Note:</strong> Adopted authority is not used.</p>
<p><strong><a name="TBLALSTAT">Authorization Required for
lstat()</a></strong></p>
<table border cellpadding="5">
<!-- cols="40 40 20" -->
<tr>
<th align="left" valign="bottom">Object Referred to</th>
<th align="left" valign="bottom">Authority Required</th>
<th align="left" valign="bottom">errno</th>
</tr>
<tr>
<td align="left" valign="top">Each directory in the path name preceding the
object</td>
<td align="center" valign="top">*X</td>
<td align="left" valign="top">EACCES</td>
</tr>
<tr>
<td align="left" valign="top">Object, if object type is not *USRPRF</td>
<td align="center" valign="top">None</td>
<td align="left" valign="top">None</td>
</tr>
<tr>
<td align="left" valign="top">Object, if object type is *USRPRF</td>
<td align="center" valign="top">Any authority greater than *EXCLUDE</td>
<td align="left" valign="top">ENOENT</td>
</tr>
</table>
<br>
<h3>Return Value</h3>
<dl compact>
<dt><em>0</em></dt>
<dd><strong>lstat()</strong> was successful. The information is returned in
<em>buf</em>.</dd>
<dt><em>-1</em></dt>
<dd><strong>lstat()</strong> was not successful. The <em>errno</em> global
variable is set to indicate the error.</dd>
</dl>
<br>
<h3><a name="HDRLSTAERR">Error Conditions</a></h3>
<p>If <strong>lstat()</strong> is not successful, <em>errno</em> usually
indicates one of the following errors. Under some conditions, <em>errno</em>
could indicate an error other than those listed here.</p>
<table cellpadding="5">
<!-- cols="25 75" -->
<tr>
<th align="left" valign="bottom">Error condition</th>
<th align="left" valign="bottom">Additional information</th>
</tr>
<tr>
<td align="left" valign="top">
<em>[<a href="unix14.htm#EACCES">EACCES</a>]</em></td>
<td align="left" valign="top">
<p>If you are accessing a remote file through the Network File System, update
operations to file permissions at the server are not reflected at the client
until updates to data that is stored locally by the Network File System take
place. (Several options on the Add Mounted File System (ADDMFS) command
determine the time between refresh operations of local data.) Access to a
remote file may also fail due to different mappings of user IDs (UID) or group
IDs (GID) on the local and remote systems.</p>
</td>
</tr>
<tr>
<td align="left" valign="top">
<em>[<a href="unix14.htm#EAGAIN">EAGAIN</a>]</em></td>
<td align="left" valign="top">
&nbsp;
</td>
</tr>
<tr>
<td align="left" valign="top">
<em>[<a href="unix14.htm#EBADFID">EBADFID</a>]</em></td>
<td align="left" valign="top">
&nbsp;
</td>
</tr>
<tr>
<td align="left" valign="top">
<em>[<a href="unix14.htm#EBADNAME">EBADNAME</a>]</em></td>
<td align="left" valign="top">
&nbsp;
</td>
</tr>
<tr>
<td align="left" valign="top">
<em>[<a href="unix14.htm#EBUSY">EBUSY</a>]</em></td>
<td align="left" valign="top">
&nbsp;
</td>
</tr>
<tr>
<td align="left" valign="top">
<em>[<a href="unix14.htm#ECONVERT">ECONVERT</a>]</em></td>
<td align="left" valign="top">
&nbsp;
</td>
</tr>
<tr>
<td align="left" valign="top">
<em>[<a href="unix14.htm#EDAMAGE">EDAMAGE</a>]</em></td>
<td align="left" valign="top">
&nbsp;
</td>
</tr>
<tr>
<td align="left" valign="top">
<em>[<a href="unix14.htm#EFAULT">EFAULT</a>]</em></td>
<td align="left" valign="top">
&nbsp;
</td>
</tr>
<tr>
<td align="left" valign="top">
<em>[<a href="unix14.htm#EFILECVT">EFILECVT</a>]</em></td>
<td align="left" valign="top">
&nbsp;
</td>
</tr>
<tr>
<td align="left" valign="top">
<em>[<a href="unix14.htm#EINTR">EINTR</a>]</em></td>
<td align="left" valign="top">
&nbsp;
</td>
</tr>
<tr>
<td align="left" valign="top">
<em>[<a href="unix14.htm#EINVAL">EINVAL</a>]</em></td>
<td align="left" valign="top">
&nbsp;
</td>
</tr>
<tr>
<td align="left" valign="top">
<em>[<a href="unix14.htm#EIO">EIO</a>]</em></td>
<td align="left" valign="top">
&nbsp;
</td>
</tr>
<tr>
<td align="left" valign="top">
<em>[<a href="unix14.htm#ELOOP">ELOOP</a>]</em></td>
<td align="left" valign="top">
&nbsp;
</td>
</tr>
<tr>
<td align="left" valign="top">
<em>[<a href="unix14.htm#ENAMETOOLONG">ENAMETOOLONG</a>]</em></td>
<td align="left" valign="top">
&nbsp;
</td>
</tr>
<tr>
<td align="left" valign="top">
<em>[<a href="unix14.htm#ENOENT">ENOENT</a>]</em></td>
<td align="left" valign="top">
&nbsp;
</td>
</tr>
<tr>
<td align="left" valign="top">
<em>[<a href="unix14.htm#ENOMEM">ENOMEM</a>]</em></td>
<td align="left" valign="top">
&nbsp;
</td>
</tr>
<tr>
<td align="left" valign="top">
<em>[<a href="unix14.htm#ENOTAVAIL">ENOTAVAIL</a>]</em></td>
<td align="left" valign="top">
&nbsp;
</td>
</tr>
<tr>
<td align="left" valign="top">
<em>[<a href="unix14.htm#ENOTDIR">ENOTDIR</a>]</em></td>
<td align="left" valign="top">
&nbsp;
</td>
</tr>
<tr>
<td align="left" valign="top">
<em>[<a href="unix14.htm#ENOSPC">ENOSPC</a>]</em></td>
<td align="left" valign="top">
&nbsp;
</td>
</tr>
<tr>
<td align="left" valign="top">
<em>[<a href="unix14.htm#ENOTSAFE">ENOTSAFE</a>]</em></td>
<td align="left" valign="top">
&nbsp;
</td>
</tr>
<tr>
<td align="left" valign="top">
<em>[<a href="unix14.htm#ENOTSUP">ENOTSUP</a>]</em></td>
<td align="left" valign="top">
&nbsp;
</td>
</tr>
<tr>
<td align="left" valign="top">
<em>[<a href="unix14.htm#EOVERFLOW">EOVERFLOW</a>]</em></td>
<td align="left" valign="top">
<p>The file size in bytes cannot be represented correctly in the structure
pointed to by <em>buf</em> (the file is larger than 2GB minus 1 byte).</p>
</td>
</tr>
<tr>
<td align="left" valign="top">
<em>[<a href="unix14.htm#EPERM">EPERM</a>]</em></td>
<td align="left" valign="top">
&nbsp;
</td>
</tr>
<tr>
<td align="left" valign="top">
<em>[<a href="unix14.htm#EROOBJ">EROOBJ</a>]</em></td>
<td align="left" valign="top">
&nbsp;
</td>
</tr>
<tr>
<td align="left" valign="top">
<em>[<a href="unix14.htm#ESTALE">ESTALE</a>]</em></td>
<td align="left" valign="top">
<p>If you are accessing a remote file through the Network File System, the file
may have been deleted at the server.</p>
</td>
</tr>
<tr>
<td align="left" valign="top">
<em>[<a href="unix14.htm#EUNKNOWN">EUNKNOWN</a>]</em></td>
<td align="left" valign="top">
&nbsp;
</td>
</tr>
</table>
<p>If interaction with a file server is required to access the object, <em>
errno</em> could indicate one of the following errors:</p>
<table cellpadding="5">
<!-- cols="25 75" -->
<tr>
<th align="left" valign="bottom">Error condition</th>
<th align="left" valign="bottom">Additional information</th>
</tr>
<tr>
<td align="left" valign="top">
<em>[<a href="unix14.htm#EADDRNOTAVAIL">EADDRNOTAVAIL</a>]</em></td>
<td align="left" valign="top">
&nbsp;
</td>
</tr>
<tr>
<td align="left" valign="top">
<em>[<a href="unix14.htm#ECONNABORTED">ECONNABORTED</a>]</em></td>
<td align="left" valign="top">
&nbsp;
</td>
</tr>
<tr>
<td align="left" valign="top">
<em>[<a href="unix14.htm#ECONNREFUSED">ECONNREFUSED</a>]</em></td>
<td align="left" valign="top">
&nbsp;
</td>
</tr>
<tr>
<td align="left" valign="top">
<em>[<a href="unix14.htm#ECONNRESET">ECONNRESET</a>]</em></td>
<td align="left" valign="top">
&nbsp;
</td>
</tr>
<tr>
<td align="left" valign="top">
<em>[<a href="unix14.htm#EHOSTDOWN">EHOSTDOWN</a>]</em></td>
<td align="left" valign="top">
&nbsp;
</td>
</tr>
<tr>
<td align="left" valign="top">
<em>[<a href="unix14.htm#EHOSTUNREACH">EHOSTUNREACH</a>]</em></td>
<td align="left" valign="top">
&nbsp;
</td>
</tr>
<tr>
<td align="left" valign="top">
<em>[<a href="unix14.htm#ENETDOWN">ENETDOWN</a>]</em></td>
<td align="left" valign="top">
&nbsp;
</td>
</tr>
<tr>
<td align="left" valign="top">
<em>[<a href="unix14.htm#ENETRESET">ENETRESET</a>]</em></td>
<td align="left" valign="top">
&nbsp;
</td>
</tr>
<tr>
<td align="left" valign="top">
<em>[<a href="unix14.htm#ENETUNREACH">ENETUNREACH</a>]</em></td>
<td align="left" valign="top">
&nbsp;
</td>
</tr>
<tr>
<td align="left" valign="top">
<em>[<a href="unix14.htm#ESTALE">ESTALE</a>]</em></td>
<td align="left" valign="top">
<p>If you are accessing a remote file through the Network File System, the file
may have been deleted at the server.</p>
</td>
</tr>
<tr>
<td align="left" valign="top">
<em>[<a href="unix14.htm#ETIMEDOUT">ETIMEDOUT</a>]</em></td>
<td align="left" valign="top">
&nbsp;
</td>
</tr>
<tr>
<td align="left" valign="top">
<em>[<a href="unix14.htm#EUNATCH">EUNATCH</a>]</em></td>
<td align="left" valign="top">
&nbsp;
</td>
</tr>
</table>
<br>
<br>
<h3>Error Messages</h3>
<p>The following messages may be sent from this function:</p>
<table width="100%" cellpadding="5">
<!-- cols="15 85" -->
<tr>
<th align="left" valign="top">Message ID</th>
<th align="left" valign="top">Error Message Text</th>
</tr>
<tr>
<td width="15%" valign="top">CPE3418 E</td>
<td width="85%" valign="top">Possible APAR condition or hardware failure.</td>
</tr>
<tr>
<td align="left" valign="top">CPFA0D4 E</td>
<td align="left" valign="top">File system error occurred. Error number
&amp;1.</td>
</tr>
<tr>
<td align="left" valign="top">CPF3CF2 E</td>
<td align="left" valign="top">Error(s) occurred during running of &amp;1
API.</td>
</tr>
<tr>
<td align="left" valign="top">CPF9872 E</td>
<td align="left" valign="top">Program or service program &amp;1 in library
&amp;2 ended. Reason code &amp;3.</td>
</tr>
</table>
<br>
<br>
<h3><a name="HDRLSTAUSG">Usage Notes</a></h3>
<ol>
<li>This function will fail with error code [ENOTSAFE] when both of the
following conditions occur:<br>
<br>
<ul>
<li>Where multiple threads exist in the job.<br>
</li>
<li>The object this function is operating on resides in a file system that is
not threadsafe. Only the following file systems are threadsafe for this
function:<br>
<br>
<ul>
<li>"Root" (/)</li>
<li>QOpenSys</li>
<li>User-defined</li>
<li>QNTC</li>
<li>QSYS.LIB</li>
<li>Independent ASP QSYS.LIB</li>
<li>QOPT</li>
<li>Network File System</li>
<li>QFileSvr.400</li>
</ul>
</li>
</ul>
<br>
</li>
<li>QOPT File System Differences<br>
<p>The value for st_atime will always be zero. The value for st_ctime will
always be the creation date and time of the file or directory.</p>
<p>If the object exists on a volume formatted in Universal Disk Format (UDF),
the authorization that is checked for the object and each directory in the path
name follows the rules described in <a href="#TBLALSTAT">Authorization Required
for lstat()</a>. If the object exists on a volume formatted in some other media
format, no authorization checks are made on the object or each directory in the
path name. The volume authorization list is checked for *USE authority
regardless of the volume media format.</p>
<p>The user, group, and other mode bits are always on for an object tha exists
on a volume not formatted in Universal Disk format (UDF).</p>
<p><strong>lstat()</strong> on /QOPT will always return 2,147,483,647 for size fields.</p>
<p><strong>lstat()</strong> on optical volumes will return the volume capacity or 2,147,483,647,
whichever is smaller.</p>
<p>The file access time is not changed.</p>
<br>
</li>
<li>Network File System Differences
<p>Local access to remote files through the Network File System may produce
unexpected results due to conditions at the server. Once a file is open,
subsequent requests to perform operations on the file can fail because file
attributes are checked at the server on each request. If permissions on the
file are made more restrictive at the server or the file is unlinked or made
unavailable by the server for another client, your operation on an open file
descriptor will fail when the local Network File System receives these updates.
The local Network File System also impacts operations that retrieve file
attributes. Recent changes at the server may not be available at your client
yet, and old values may be returned from operations. (Several options on the
Add Mounted File System (ADDMFS) command determine the time between refresh
operations of local data.)</p>
<br>
</li>
<li>QNetWare File System Differences
<p>The QNetWare file system does not fully support mode bits. See <a href=
"../rzaef/rzaefoverview.htm">NetWare on iSeries</a> for more information.</p>
<br>
</li>
<li>This function will fail with the [EOVERFLOW] error if the file size in
bytes cannot be represented correctly in the structure pointed to by buf (the
file is larger than 2GB minus 1 byte).<br>
<br>
</li>
<li>When you develop in C-based languages and this function is compiled with
_LARGE_FILES defined, it will be mapped to <strong>lstat64()</strong>. Note
that the type of the buf parameter, <samp>struct stat</samp>, also will be
mapped to type <samp>struct stat64</samp>.</li>
</ol>
<br>
<h3>Related Information</h3>
<ul>
<li>The &lt;<strong>sys/stat.h</strong>&gt; file (see <a href="unix13.htm">
Header Files for UNIX-Type Functions</a>)
</li>
<li>The &lt;<strong>sys/types.h</strong>&gt; file (see <a href="unix13.htm">
Header Files for UNIX-Type Functions</a>)
</li>
<li><a href="chmod.htm">chmod()</a>--Change File Authorizations
</li>
<li><a href="chown.htm">chown()</a>--Change Owner and Group of File
</li>
<li><a href="creat.htm">creat()</a>--Create or Rewrite File
</li>
<li><a href="dup.htm">dup()</a>--Duplicate Open File Descriptor
</li>
<li>
<a href="fclear.htm">fclear()</a>--Write (Binary Zeros) to Descriptor
</li>
<li><a href="fclear64.htm">fclear64()</a>--Write (Binary Zeros) to Descriptor
(Large File Enabled)
</li>
<li><a href="fcntl.htm">fcntl()</a>--Perform File Control Command
</li>
<li><a href="fstat.htm">fstat()</a>--Get File Information by Descriptor
</li>
<li><a href="link.htm">link()</a>--Create Link to File
</li>
<li><a href="mkdir.htm">mkdir()</a>--Make Directory
</li>
<li><a href="open.htm">open()</a>--Open File
</li>
<li><a href="lstatu.htm">QlgLstat()</a>--Get File or Link Information
</li>
<li><a href="read.htm">read()</a>--Read from Descriptor
</li>
<li><a href="readlink.htm">readlink()</a>--Read Value of Symbolic Link
</li>
<li><a href="stat.htm">stat()</a>--Get File Information
</li>
<li><a href="symlink.htm">symlink()</a>--Make Symbolic Link
</li>
<li><a href="unlink.htm">unlink()</a>--Remove Link to File
</li>
<li><a href="utime.htm">utime()</a>--Set File Access and Modification Times
</li>
<li><a href="write.htm">write()</a>--Write to Descriptor</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 provides status information for a file:</p>
<pre>
#include &lt;sys/types.h&gt;
#include &lt;sys/stat.h&gt;
#include &lt;stdio.h&gt;
#include &lt;fcntl.h&gt;
#include &lt;unistd.h&gt;
#include &lt;time.h&gt;
#include &lt;stdio.h&gt;
main() {
char fn[]="temp.file", ln[]="temp.link";
struct stat info;
int file_descriptor;
if ((file_descriptor = creat(fn, S_IWUSR)) &lt; 0)
perror("creat() error");
else {
close(file_descriptor);
if (link(fn, ln) != 0)
perror("link() error");
else {
if (lstat(ln, &amp;info) != 0)
perror("lstat() error");
else {
puts("lstat() returned:");
printf(" inode: %d\n", (int) info.st_ino);
printf(" dev id: %d\n", (int) info.st_dev);
printf(" mode: %08x\n", info.st_mode);
printf(" links: %d\n", info.st_nlink);
printf(" uid: %d\n", (int) info.st_uid);
printf(" gid: %d\n", (int) info.st_gid);
}
unlink(ln);
}
unlink(fn);
}
}
</pre>
<p><strong>Output:</strong></p>
<pre>
lstat() returned:
inode: 3022
dev id: 1
mode: 00008080
links: 2
uid: 137
gid: 500
</pre>
<br>
<hr>
API introduced: V3R1
<hr>
<center>
<table cellpadding="2" cellspacing="2">
<tr align="center">
<td valign="middle" align="center"><a href="#Top_Of_Page">Top</a> | <a href=
"unix.htm">UNIX-Type APIs</a> | <a href="aplist.htm">APIs by category</a></td>
</tr>
</table>
</center>
</body>
</html>
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