friedkiwi/ibm-information-center
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity
8826eae394
ibm-information-center/dist/eclipse/plugins/i5OS.ic.apis_5.4.0.1/chmod.htm

1030 lines
24 KiB
HTML
Raw Normal View History

Add readme and dist folders
2024-04-02 14:02:31 +00:00
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<meta name="Copyright" content="Copyright (c) 2006 by IBM Corporation">
<title>chmod()--Change File Authorizations</title>
<!-- Begin Header Records ========================================== -->
<!-- All rights reserved. Licensed Materials Property of IBM -->
<!-- US Government Users Restricted Rights -->
<!-- Use, duplication or disclosure restricted by -->
<!-- GSA ADP Schedule Contract with IBM Corp. -->
<!-- Change History: -->
<!-- YYMMDD USERID Change description -->
<!-- Unix2 SCRIPT J converted by B2H R4.1 (346) (CMS) by V2KEA304 -->
<!-- at RCHVMW2 on 17 Feb 1999 at 11:05:09 -->
<!-- 010314 JTROUS Modify S_ISGID description, V5R2, 98686 -->
<!-- 010320 JTROUS Include Journal ERRNOs, should have in V5R1 -->
<!-- and changed example to check errno on each IFS -->
<!-- call, but did not change flag these latter chgs -->
<!-- 011022 JTROUS Changes from API Review 1, V5R2 -->
<!-- 020131 JTROUS Changes from API Review 3, V5R2 -->
<!-- 020618 EMIG Updates for NFS threadsafety, V5R3 -->
<!-- 020715 Rosckes Add table to include special save file case -->
<!-- 020514 JET This file has undergone html cleanup -->
<!-- 020718 MFENLON: updated for QFileSvr.400 threadsafety, V5R3 -->
<!-- 020829 RTHEIS : S_ISVTX mode bit, V5R3 -->
<!-- 050321 JTROUS: fix enums, no change flag, V5R4 -->
<!-- End Header Records -->
<link rel="stylesheet" type="text/css" href="../rzahg/ic.css">
</head>
<body>
<!--Java sync-link-->
<script language="Javascript" src="../rzahg/synch.js" type="text/javascript">
</script>
<a name="Top_Of_Page"></a>
<h2>chmod()--Change File Authorizations</h2>
<div class="box" style="width: 70%;">
<br>
&nbsp;&nbsp;Syntax<br>
<pre>
#include &lt;sys/stat.h&gt;
int chmod(const char <em>*path</em>, mode_t <em>mode</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="#HDRCHMODUS">Usage
Notes</a>.<br>
<!-- iddvc RMBR -->
<br>
</div>
<p>The <strong>chmod()</strong> function changes S_ISUID, S_ISGID,
S_ISVTX,
and the
permission bits of the file or directory specified in <em>path</em> to the
corresponding bits specified in <em>mode</em>. If the named file is a symbolic
link, <strong>chmod()</strong> resolves the symbolic link. <strong>
chmod()</strong> has no effect on file descriptions for files that are open at
the time <strong>chmod()</strong> is called.</p>
<p>When <strong>chmod()</strong> is successful it updates the change time of
the file.</p>
<p>If the file is checked out by another user (someone other than the user
profile of the current job), <strong>chmod()</strong> fails with the [EBUSY]
error.</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 whose mode
is being changed.
<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="chmodu.htm">QlgChmod()--Change File Authorizations</a> for a
description and an example of supplying the <em>path</em> in any CCSID.</p>
<br>
</dd>
<dt><strong><em>mode</em></strong></dt>
<dd>(Input) Bits that define S_ISUID, S_ISGID,
S_ISVTX,
and the access permissions of
the file.
<p>The <em>mode</em> argument is created with one of the following symbols
defined in the &lt;<strong>sys/stat.h</strong>&gt; include file.
See the <a href="#HDRCHMODUS">Usage Notes</a> for the file system differences
regarding these symbols.
</p>
<dl compact>
<dt><em>S_IRUSR</em></dt>
<dd>Read permission for the file owner</dd>
<dt><em>S_IWUSR</em></dt>
<dd>Write permission for the file owner</dd>
<dt><em>S_IXUSR</em></dt>
<dd>Search permission (for a directory) or execute permission (for a file) for
the file owner</dd>
<dt><em>S_IRWXU</em></dt>
<dd>Read, write, and search or execute for the file owner. S_IRWXU is the
bitwise inclusive OR of S_IRUSR, S_IWUSR, and S_IXUSR</dd>
<dt><em>S_IRGRP</em></dt>
<dd>Read permission for the file's group</dd>
<dt><em>S_IWGRP</em></dt>
<dd>Write permission for the file's group</dd>
<dt><em>S_IXGRP</em></dt>
<dd>Search permission (for a directory) or execute permission (for a file) for
the file's group</dd>
<dt><em>S_IRWXG</em></dt>
<dd>Read, write, and search or execute permission for the file's group. S_IRWXG
is the bitwise inclusive OR of S_IRGRP, S_IWGRP, and S_IXGRP</dd>
<dt><em>S_IROTH</em></dt>
<dd>General read permission</dd>
<dt><em>S_IWOTH</em></dt>
<dd>General write permission</dd>
<dt><em>S_IXOTH</em></dt>
<dd>General search permission (for a directory) or general execute permission
(for a file)</dd>
<dt><em>S_IRWXO</em></dt>
<dd>General read, write, and search or execute permission. S_IRWXO is the
bitwise inclusive OR of S_IROTH, S_IWOTH, and S_IXOTH</dd>
<dt><em>S_ISUID</em></dt>
<dd>Set effective user ID at execution time. This bit is ignored if the object
specified by <em>path</em> is a directory.</dd>
<dt><em>S_ISGID</em></dt>
<dd>Set effective group ID at execution time. See <a href="#HDRCHMODUS">Usage
Notes</a> for more information if the object specified by <em>path</em> is a
directory.</dd>
<dt><em>S_ISVTX</em></dt>
<dd>Restricted renames and unlinks for objects within a directory. Objects can be linked into
a directory that has this bit set on, but cannot be renamed or unlinked from it
unless one or more of the following are true for the user performing the operation:
<ul><li>The user is the owner of the object.</li>
<li>The user is the owner of the directory.</li>
<li>The user has all object (*ALLOBJ) special authority.</li>
</ul>
This restriction only applies to directories in the "root" (/), QOpenSys, and user-defined
file systems. Other types of object and directories in other file systems may have
this bit on, however, it will be ignored.</dd>
</dl>
<p>If bits other than the bits listed above are set in <em>mode</em>, <strong>
chmod()</strong> returns the [EINVAL] error.</p>
</dd>
</dl>
<br>
<h3>Authorities</h3>
<p><strong>Note:</strong> Adopted authority is not used.</p>
<strong><a name="TBLACHMOD">Authorization required for chmod() (excluding
QDLS, QSYS.LIB, and Independent ASP QSYS.LIB)</a></strong><br>
<table border cellpadding="5" width="80%">
<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</td>
<td align="center" valign="top">Owner (see <strong>Note</strong>)</td>
<td align="left" valign="top">EPERM</td>
</tr>
<tr>
<td align="left" valign="top" colspan="3"><strong>Note:</strong> You do not
need the listed authority if you have *ALLOBJ special authority.</td>
</tr>
</table>
<br>
<br>
<strong><a name="TBLACHMOD3">Authorization required for chmod() in the QDLS
File System</a></strong><br>
<table border cellpadding="5" width="80%">
<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</td>
<td align="center" valign="top">Owner or *ALL</td>
<td align="left" valign="top">EACCES</td>
</tr>
</table>
<br>
<br>
<strong><a name="TBLACHMOD2">Authorization required for chmod() in the QSYS.LIB and Independent ASP QSYS.LIB
file systems.
</a></strong><br>
<table border cellpadding="5" width="80%">
<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">The parent directory of the
object if the object is a save file</td>
<td align="center" valign="top">*RX</td>
<td align="left" valign="top">EPERM</td>
</tr>
<tr>
<td align="left" valign="top">Object</td>
<td align="center" valign="top">Owner (see <strong>Note</strong>)</td>
<td align="left" valign="top">EPERM</td>
</tr>
<tr>
<td align="left" valign="top" colspan="3"><strong>Note:</strong> You do not
need the listed authority if you have *ALLOBJ special authority.</td>
</tr>
</table>
<br>
<br>
<h3>Return Value</h3>
<dl compact>
<dt><em>0</em></dt>
<dd><strong>chmod()</strong> was successful.</dd>
<dt><em>-1</em></dt>
<dd><strong>chmod()</strong> was not successful. The <em>errno</em> global
variable is set to indicate the error.</dd>
</dl>
<br>
<h3>Error Conditions</h3>
<p>If <strong>chmod()</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#EJRNDAMAGE">EJRNDAMAGE</a>]</em></td>
<td align="left" valign="top">
&nbsp;
</td>
</tr>
<tr>
<td align="left" valign="top">
<em>[<a href="unix14.htm#EJRNENTTOOLONG">EJRNENTTOOLONG</a>]</em></td>
<td align="left" valign="top">
&nbsp;
</td>
</tr>
<tr>
<td align="left" valign="top">
<em>[<a href="unix14.htm#EJRNINACTIVE">EJRNINACTIVE</a>]</em></td>
<td align="left" valign="top">
&nbsp;
</td>
</tr>
<tr>
<td align="left" valign="top">
<em>[<a href="unix14.htm#EJRNRCVSPC">EJRNRCVSPC</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#ENEWJRN">ENEWJRN</a>]</em></td>
<td align="left" valign="top">
&nbsp;
</td>
</tr>
<tr>
<td align="left" valign="top">
<em>[<a href="unix14.htm#ENEWJRNRCV">ENEWJRNRCV</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#ENOSPC">ENOSPC</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#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#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 also 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#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%">
<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 valign="top">CPFA0D4 E</td>
<td valign="top">File system error occurred. Error number &amp;1.</td>
</tr>
<tr>
<td valign="top">CPF3CF2 E</td>
<td valign="top">Error(s) occurred during running of &amp;1 API.</td>
</tr>
<tr>
<td valign="top">CPF9872 E</td>
<td 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="HDRCHMODUS">Usage Notes</a></h3>
<ol type="1">
<li>This function will fail with error code [ENOTSAFE] when all the following
conditions are true:<br>
<br>
<ul>
<li>Where multiple threads exist in the job.<br>
</li>
<li>The object on which this function is operating 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>"Root" (/), QOpenSys, and User-Defined File System Differences
<p>If the object has a primary group, it must match the primary group ID or one
of the supplemental group IDs of the caller of the API; otherwise, the S_ISGID
bit is turned off.</p>
<br>
</li>
<li>QSYS.LIB and independent ASP QSYS.LIB File System Differences
<p><strong>chmod()</strong> is not supported for member (.MBR) objects.</p>
<p><strong>chmod()</strong> returns EBUSY if the object is allocated in
another job.</p>
<p>QSYS.LIB and independent ASP QSYS.LIB do not support setting the S_ISUID
(set-user-ID), S_ISGID (set-group_ID), and
S_ISVTX (restricted rename and unlink)
bits. If they are turned on in the
mode parameter, they are ignored.</p>
<br>
</li>
<li>QDLS File System Differences
<p>Changing the permissions of the /QDLS directory (the root folder) is not
allowed. If an attempt is made to change the permissions, error ENOTSUP is
returned.</p>
<p>&quot;Group&quot; rights are not set if there is no current group.</p>
<p> QDLS does not support setting the S_ISUID, S_ISGID, and
S_ISVTX
bits. If they are
turned on in the mode parameter, they are ignored.</p>
<br>
</li>
<li>QOPT File System Differences
<p>Changing the permissions is allowed only for an object that exists on a
volume formatted in Universal Disk Format (UDF). For all other media formats,
ENOTSUP is returned.</p>
<p>In addition to the authorization checks described in <a href="#TBLACHMOD">
Authorization Required for chmod()</a>, the volume authorization list is
checked for *CHANGE authority.</p>
<p>QOPT does not support setting the S_ISUID, S_ISGID, and
S_ISVTX
bits for any optical
media format. If they are turned on in the mode parameter, ENOTSUP is
returned.</p>
<br>
</li>
<li>QNetWare File System Differences
<p>The QNetWare file system does not fully support <strong>chmod()</strong>.
See <a href="../rzaef/rzaefoverview.htm">NetWare on iSeries</a> for more
information.</p>
<p>QNetWare supports the S_ISUID and S_ISGID
bits by passing them to the server
and surfacing them to the caller. Some versions of NetWare may support the bits
and others may not.</p>
<p>QNetWare does not support setting the S_ISVTX bit. If it is turned on in the
mode parameter, ENOTSUP is returned.
</p>
<br>
</li>
<li>QFileSvr.400 Differences
<p>QFileSvr.400 supports the S_ISUID, S_ISGID, and
S_ISVTX
bits by passing them to the
server and surfacing them to the caller.</p>
<br>
</li>
<li>Network File System Differences
<p>The NFS client supports the S_ISUID, S_ISGID, and
S_ISVTX
bits by passing them to the
server over the network and surfacing them to the caller. Whether a particular
network file system supports the setting of these bits depends on the server.
Most servers have the capability of masking off the
S_ISUID and S_ISGID
bits if the NOSUID option
is specified on the export. The default, however, is to support these
two
bits.
</p>
<br>
</li>
<li>QNTC File System Differences
<p><strong>chmod()</strong> does not update the Windows NT server access
control lists that control the authority of users to the file or directory. The
mode settings are ignored.</p>
<br>
</li>
<li>S_ISGID bit of a directory in "root" (/), QOpenSys, or User-Defined File System
<p>The S_ISGID bit of the directory affects what the group ID (GID) is for
objects that are created in the directory. If the S_ISGID bit of the parent
directory is off, the group ID (GID) is set to the effective GID of the thread
creating the object. If the S_ISGID bit of the parent directory is on, the
group ID (GID) of the new object is set to the GID of the parent directory. For
all other file systems, the GID of the new object is set to the GID of the
parent directory.</p>
</li>
</ol>
<br>
<h3>Related Information</h3>
<ul>
<li>The &lt;<strong>sys/types.h</strong>&gt; file (see <a href="unix13.htm">
Header Files for UNIX-Type Functions</a>)
</li>
<li>The &lt;<strong>sys/stat.h</strong>&gt; file (see <a href="unix13.htm">
Header Files for UNIX-Type Functions</a>)
</li>
<li><a href="chown.htm">chown()</a>--Change Owner and Group of File
</li>
<li><a href="fchmod.htm">fchmod()</a>--Change File Authorizations by
Descriptor
</li>
<li><a href="mkdir.htm">mkdir()</a>--Make Directory
</li>
<li><a href="open.htm">open()</a>--Open File
</li>
<li><a href="stat.htm">stat()</a>--Get File Information
</li>
<li><a href="chmodu.htm">QlgChmod()</a>--Change File Authorizations</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 changes the permissions for a file:</p>
<pre>
#include &lt;stdio.h&gt;
#include &lt;sys/stat.h&gt;
#include &lt;sys/types.h&gt;
main() {
char fn[]=&quot;temp.file&quot;;
int file_descriptor;
struct stat info;
if ((file_descriptor = creat(fn, S_IWUSR)) == -1)
perror(&quot;creat() error&quot;);
else {
if (stat(fn, &amp;info)!= 0)
perror("stat() error");
else {
printf("original permissions were: %08o\n", info.st_mode);
}
if (chmod(fn, S_IRWXU|S_IRWXG) != 0)
perror("chmod() error");
else {
if (stat(fn, &amp;info)!= 0)
perror("stat() error");
else {
printf("after chmod(), permissions are: %08o\n", info.st_mode);
}
}
if (close(file_descriptor)!= 0)
perror("close() error");
if (unlink(fn)!= 0)
perror("unlink() error");
}
}
</pre>
<p><strong>Output:</strong></p>
<pre>
original permissions were: 00100200
after chmod(), permissions are: 00100770
</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>
Reference in New Issue Copy Permalink