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<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2 Final//EN"><html><head><!-- Copyright 1997 The Open Group, All Rights Reserved --><title>endutxent</title></head><body bgcolor=white><center><font size=2>The Single UNIX ® Specification, Version 2<br>Copyright © 1997 The Open Group</font></center><hr size=2 noshade><h4><a name = "tag_000_005_788"> </a>NAME</h4><blockquote>endutxent, getutxent, getutxid, getutxline, pututxline, setutxent- user accounting database functions</blockquote><h4><a name = "tag_000_005_789"> </a>SYNOPSIS</h4><blockquote><pre><code>#include <<a href="utmpx.h.html">utmpx.h</a>>void endutxent(void);struct utmpx *getutxent(void);struct utmpx *getutxid(const struct utmpx *<i>id</i>);struct utmpx *getutxline(const struct utmpx *<i>line</i>);struct utmpx *pututxline(const struct utmpx *<i>utmpx</i>);void setutxent(void);</code></pre></blockquote><h4><a name = "tag_000_005_790"> </a>DESCRIPTION</h4><blockquote>These functions provide access to the user accounting database.<p>The<i><a href="getutxent.html">getutxent()</a></i>function reads in the next entry from the user accountingdatabase. If the database is not already open, it opens it. If it reachesthe end of the database, it fails.<p>The<i>getutxid()</i>function searches forward from the current point in the database. If the<b>ut_type</b> value of the <b>utmpx</b> structure pointed to by <i>id</i> isBOOT_TIME, OLD_TIME or NEW_TIME, then it stops when it finds anentry with a matching <b>ut_type</b> value.If the <b>ut_type</b> value is INIT_PROCESS, LOGIN_PROCESS, USER_PROCESS,or DEAD_PROCESS, then it stops when it finds an entry whose type is one ofthese four and whose <b>ut_id</b> member matches the <b>ut_id</b> member ofthe <b>utmpx</b> structure pointed to by <i>id</i>. If the end of the databaseis reached without a match,<i>getutxid()</i>fails.<p>The<i>getutxid()</i>or<i>getutxline()</i>may cache data.For this reason, to use<i>getutxline()</i>to search for multiple occurrences, it is necessary to zero out the staticdata after each success, or<i>getutxline()</i>could just return a pointer to the same <b>utmpx</b> structure over and overagain.<p>There is one exception to the rule about removing the structure before furtherreads are done. The implicit read done by<i><a href="pututxline.html">pututxline()</a></i>(if it finds that it is not already at the correct place in the useraccounting database) will not modify the static structure returned by<i><a href="getutxent.html">getutxent()</a></i>,<i>getutxid()</i>or<i>getutxline()</i>,if the application has just modified this structure and passed the pointerback to<i><a href="pututxline.html">pututxline()</a></i>.<p>For all entries that match a request, the<b>ut_type</b>member indicates the type of the entry. Other members of the entry willcontain meaningful data based on the value of the<b>ut_type</b>member as follows:<pre><table bordercolor=#000000 border=1 align=center><tr valign=top><th align=center><b>ut_type Member</b><th align=center><b>Other Members with Meaningful Data</b><tr valign=top><td align=left>EMPTY<td align=left>No others<tr valign=top><td align=left>BOOT_TIME<td align=left><b>ut_tv</b><tr valign=top><td align=left>OLD_TIME<td align=left><b>ut_tv</b><tr valign=top><td align=left>NEW_TIME<td align=left><b>ut_tv</b><tr valign=top><td align=left>USER_PROCESS<td align=left><b>ut_id</b>, <b>ut_user</b> (login name of the user), <b>ut_line</b>, <b>ut_pid</b>, <b>ut_tv</b><tr valign=top><td align=left>INIT_PROCESS<td align=left><b>ut_id</b>, <b>ut_pid</b>, <b>ut_tv</b><tr valign=top><td align=left>LOGIN_PROCESS<td align=left><b>ut_id</b>, <b>ut_user</b> (implementation-dependent name of the login process), <b>ut_pid</b>, <b>ut_tv</b><tr valign=top><td align=left>DEAD_PROCESS<td align=left><b>ut_id</b>, <b>ut_pid</b>, <b>ut_tv</b></table></pre><p>The<i>getutxline()</i>function searches forward from the current point in the database until itfinds an entry of the type LOGIN_PROCESS or USER_PROCESS which also has a<b>ut_line</b> value matching that in the <b>utmpx</b> structure pointed to by<i>line</i>. If the end of the database is reached without a match,<i>getutxline()</i>fails.<p>If the process has appropriate privileges, the<i><a href="pututxline.html">pututxline()</a></i>function writes out the structure into the user accounting database.It uses<i>getutxid()</i>to search for a record that satisfies the request. If this search succeeds,then the entry is replaced. Otherwise, a new entry is made at the end of theuser accounting database.<p>The<i><a href="setutxent.html">setutxent()</a></i>function resets the input to the beginning of the database. This should bedone before each search for a new entry if it is desired that the entiredatabase be examined.<p>The<i>endutxent()</i>function closes the user accounting database.<p>These interfaces need not be reentrant.</blockquote><h4><a name = "tag_000_005_791"> </a>RETURN VALUE</h4><blockquote>Upon successful completion,<i><a href="getutxent.html">getutxent()</a></i>,<i>getutxid()</i>and<i>getutxline()</i>return a pointer to a <b>utmpx</b> structure containing a copy of the requestedentry in the user accounting database. Otherwise a null pointer is returned.<p>The return value may point to a static area which is overwritten by asubsequent call to<i>getutxid()</i>or<i>getutxline()</i>.<p>Upon successful completion,<i><a href="pututxline.html">pututxline()</a></i>returns a pointer to a <b>utmpx</b> structure containing a copy of the entryadded to the user accounting database. Otherwise a null pointer is returned.<p>The<i>endutxent()</i>and<i><a href="setutxent.html">setutxent()</a></i>functions return no value.</blockquote><h4><a name = "tag_000_005_792"> </a>ERRORS</h4><blockquote>No errors are defined for the<i>endutxent()</i>,<i><a href="getutxent.html">getutxent()</a></i>,<i>getutxid()</i>,<i>getutxline()</i>and<i><a href="setutxent.html">setutxent()</a></i>functions.<p>The<i><a href="pututxline.html">pututxline()</a></i>function may fail if:<dl compact><dt>[EPERM]<dd>The process does not have appropriate privileges.</dl></blockquote><h4><a name = "tag_000_005_793"> </a>EXAMPLES</h4><blockquote>None.</blockquote><h4><a name = "tag_000_005_794"> </a>APPLICATION USAGE</h4><blockquote>The sizes of the arrays in thestructure can be found using the <b>sizeof</b> operator.</blockquote><h4><a name = "tag_000_005_795"> </a>FUTURE DIRECTIONS</h4><blockquote>None.</blockquote><h4><a name = "tag_000_005_796"> </a>SEE ALSO</h4><blockquote><i><a href="utmpx.h.html"><utmpx.h></a></i>.</blockquote><hr size=2 noshade><center><font size=2>UNIX ® is a registered Trademark of The Open Group.<br>Copyright © 1997 The Open Group<br> [ <a href="../index.html">Main Index</a> | <a href="../xshix.html">XSH</a> | <a href="../xcuix.html">XCU</a> | <a href="../xbdix.html">XBD</a> | <a href="../cursesix.html">XCURSES</a> | <a href="../xnsix.html">XNS</a> ]</font></center><hr size=2 noshade></body></html>⌨️ 快捷键说明
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