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<html><head><title>User::grent (Perl in a Nutshell, 2nd Edition)</title><link rel="stylesheet" type="text/css" href="../style/style1.css" /><meta name="DC.Creator" content="Stephen Spainhour" /><meta name="DC.Format" content="text/xml" scheme="MIME" /><meta name="DC.Language" content="en-US" /><meta name="DC.Publisher" content="O'Reilly & Associates, Inc." /><meta name="DC.Source" scheme="ISBN" content="0596002416L" /><meta name="DC.Subject.Keyword" content="stuff" /><meta name="DC.Title" content="Perl in a Nutshell, 2nd Edition" /><meta name="DC.Type" content="Text.Monograph" /></head><body bgcolor="#ffffff"><img src="gifs/smbanner.gif" usemap="#banner-map" border="0" alt="Book Home" /><map name="banner-map"><area shape="rect" coords="1,-2,616,66" href="index.htm" alt="Java and XSLT" /><area shape="rect" coords="629,-11,726,25" href="jobjects/fsearch.htm" alt="Search this book" /></map><div class="navbar"><table width="684" border="0"><tr><td align="left" valign="top" width="228"><a href="ch08_228.htm"><img src="../gifs/txtpreva.gif" alt="Previous" border="0" /></a></td><td align="center" valign="top" width="228" /><td align="right" valign="top" width="228"><a href="ch08_230.htm"><img src="../gifs/txtnexta.gif" alt="Next" border="0" /></a></td></tr></table></div><h2 class="sect1">8.229. User::grent</h2><p><a name="INDEX-1600" />Overrides core<tt class="literal">getgrent</tt>, <tt class="literal">getgruid</tt>, and<tt class="literal">getgrnam</tt> functions with versions that returnUser::grent objects. The object returned has methods with the samenames as the structure fields they return. That is, to return thefield <em class="emphasis">name</em>, use the <tt class="literal">name</tt>method:</p><blockquote><pre class="code">use User::grent;$gr = getgrgid(0) or die "No group zero";if ( $gr->name eq 'wheel' && @{$gr->members} > 1 ) { print "gid zero name wheel, with other members";}</pre></blockquote><p>The field names (and therefore the method names) are the same as thenames of the fields in the <em class="emphasis">group</em> structure fromthe C file <em class="emphasis">grp.h</em>: <em class="emphasis">name</em>,<em class="emphasis">passwd</em>, <em class="emphasis">gid</em>, and<em class="emphasis">members</em> (not <em class="emphasis">mem</em>). Thefirst three return scalars, the last an array reference. You canaccess the fields with the methods or by importing the fields intoyour namespace with the :FIELDS import tag and prepending<tt class="literal">gr_</tt> to the method name (for example,<tt class="literal">gr_name</tt>). Exports four functions.</p><div class="refentry"><table width="515" border="0" cellpadding="5"><tr><td align="left"><font size="+1"><b>getgr</b></font></td><td align="right"><i></i></td></tr></table><hr width="515" size="3" noshade="true" align="left" color="black" /><pre>$<em class="replaceable">gr</em>->getgr(<em class="replaceable">arg</em>)</pre><p>Frontend that forwards a numeric <em class="replaceable">arg</em> to<tt class="literal">getgrid</tt> and other <em class="replaceable"><tt>arg</tt></em>sto <tt class="literal">getgrname</tt>.</p></div><div class="refentry"><table width="515" border="0" cellpadding="5"><tr><td align="left"><font size="+1"><b>getgrent</b></font></td><td align="right"><i></i></td></tr></table><hr width="515" size="3" noshade="true" align="left" color="black" /><pre>$<em class="replaceable">gr</em> = getgrent( )</pre><p>Successive calls to <tt class="literal">getgrent</tt> return objectsrepresenting successive entries from the group file.</p></div><div class="refentry"><table width="515" border="0" cellpadding="5"><tr><td align="left"><font size="+1"><b>getgrgid</b></font></td><td align="right"><i></i></td></tr></table><hr width="515" size="3" noshade="true" align="left" color="black" /><pre>$<em class="replaceable">gr</em> = getgrgid(<em class="replaceable">gid</em>)</pre><p>Accesses the group file by group ID <em class="replaceable">gid</em>.</p></div><div class="refentry"><table width="515" border="0" cellpadding="5"><tr><td align="left"><font size="+1"><b>getgrnam</b></font></td><td align="right"><i></i></td></tr></table><hr width="515" size="3" noshade="true" align="left" color="black" /><pre>$<em class="replaceable">gr</em> = getgrnam(<em class="replaceable">gname</em>)</pre><p>Accesses the group file by group name<em class="replaceable"><tt>gname</tt></em>.</p></div><hr width="684" align="left" /><div class="navbar"><table width="684" border="0"><tr><td align="left" valign="top" width="228"><a href="ch08_228.htm"><img src="../gifs/txtpreva.gif" alt="Previous" border="0" /></a></td><td align="center" valign="top" width="228"><a href="index.htm"><img src="../gifs/txthome.gif" alt="Home" border="0" /></a></td><td align="right" valign="top" width="228"><a href="ch08_230.htm"><img src="../gifs/txtnexta.gif" alt="Next" border="0" /></a></td></tr><tr><td align="left" valign="top" width="228">8.228. 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