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2989 Eliminate use of LOGNAME_MAX in ON
1166 useradd have warning with name more 8 chars

@@ -1,6 +1,7 @@
 '\" te
+.\" Copyright (c) 2013 Gary Mills
 .\" Copyright (c) 2004 Sun Microsystems, Inc.  All Rights Reserved.
 .\" Copyright 1989 AT&T
 .\" Portions Copyright (c) 1992, X/Open Company Limited.  All Rights Reserved.
 .\" Sun Microsystems, Inc. gratefully acknowledges The Open Group for permission to reproduce portions of its copyrighted documentation. Original documentation from The Open Group can be obtained online at

@@ -7,11 +8,11 @@
 .\" The Institute of Electrical and Electronics Engineers and The Open Group, have given us permission to reprint portions of their documentation. In the following statement, the phrase "this text" refers to portions of the system documentation. Portions of this text are reprinted and reproduced in electronic form in the Sun OS Reference Manual, from IEEE Std 1003.1, 2004 Edition, Standard for Information Technology -- Portable Operating System Interface (POSIX), The Open Group Base Specifications Issue 6, Copyright (C) 2001-2004 by the Institute of Electrical and Electronics Engineers, Inc and The Open Group. In the event of any discrepancy between these versions and the original IEEE and The Open Group Standard, the original IEEE and The Open Group Standard is the referee document. The original Standard can be obtained online at
 .\"  This notice shall appear on any product containing this material.
 .\" The contents of this file are subject to the terms of the Common Development and Distribution License (the "License").  You may not use this file except in compliance with the License.
 .\" You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE or  See the License for the specific language governing permissions and limitations under the License.
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-.TH GETLOGIN 3C "May 18, 2004"
+.TH GETLOGIN 3C "May 25, 2013"
 getlogin, getlogin_r \- get login name

@@ -40,20 +41,42 @@
 \fB/var/adm/utmpx\fR. It can be used in conjunction with \fBgetpwnam\fR(3C) to
 locate the correct password file entry when the same user \fBID\fR is shared by
 several login names.
+The login name plus the terminating null byte can be up to 33 characters
+in length.
+Newly-compiled programs should use the \fBLOGIN_NAME_MAX\fR symbol,
+defined in <\fBlimits.h\fR>, to size the buffer.
+Older programs that call \fBgetlogin()\fR  expect only the legacy
+9-character length.
+These automatically link to a version of the \fBgetlogin()\fR functions that
+truncates longer login names.
+It's also possible to compile new programs that link to truncating versions
+of these functions by defining \fB__USE_LEGACY_LOGNAME__\fR in the
+compile environment.
+Some older programs will correctly handle long login names returned
+by the \fBgetlogin()\fR function.
+For this case, the user compatibility library
+\fB/usr/lib/\fR redirects to a version of the \fBgetlogin()\fR
+function that returns the long name.
+This library should be added to such an application
+at runtime using \fBLD_PRELOAD\fR.
 If \fBgetlogin()\fR is called within a process that is not attached to a
 terminal, it returns a null pointer. The correct procedure for determining the
 login name is to call \fBcuserid\fR(3C), or to call \fBgetlogin()\fR and if it
 fails to call \fBgetpwuid\fR(3C).
 The \fBgetlogin_r()\fR function has the same functionality as \fBgetlogin()\fR
 except that the caller must supply a buffer \fIname\fR with length
 \fInamelen\fR to store the result.  The \fIname\fR buffer must be at least
-\fB_POSIX_LOGIN_NAME_MAX\fR bytes in size (defined in <\fBlimits.h\fR>). The
+\fBLOGIN_NAME_MAX\fR bytes in size (defined in <\fBlimits.h\fR>). The
 POSIX version (see \fBstandards\fR(5)) of \fBgetlogin_r()\fR takes a
 \fInamesize\fR parameter of type \fBsize_t\fR.

@@ -149,10 +172,28 @@
 .RS 18n
 user access and administration information
+.sp 2
+.RS 18n
+A compatibility library that returns long login names to older applications.
+.sp 2
+.RS 18n
+A 64-bit compatibility library to return long login names.
 See \fBattributes\fR(5) for descriptions of the following attributes: