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2989 Eliminate use of LOGNAME_MAX in ON
1166 useradd have warning with name more 8 chars
   1 '\" te

   2 .\" Copyright (c) 2004 Sun Microsystems, Inc.  All Rights Reserved.
   3 .\" Copyright 1989 AT&T
   4 .\" Portions Copyright (c) 1992, X/Open Company Limited.  All Rights Reserved.
   5 .\" 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
   6 .\" http://www.opengroup.org/bookstore/.
   7 .\" 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 http://www.opengroup.org/unix/online.html.
   8 .\"  This notice shall appear on any product containing this material.
   9 .\" 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.
  10 .\" You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE or http://www.opensolaris.org/os/licensing.  See the License for the specific language governing permissions and limitations under the License.
  11 .\" When distributing Covered Code, include this CDDL HEADER in each file and include the License file at usr/src/OPENSOLARIS.LICENSE.  If applicable, add the following below this CDDL HEADER, with the fields enclosed by brackets "[]" replaced with your own identifying information: Portions Copyright [yyyy] [name of copyright owner]
  12 .TH GETLOGIN 3C "May 18, 2004"
  13 .SH NAME
  14 getlogin, getlogin_r \- get login name
  15 .SH SYNOPSIS
  16 .LP
  17 .nf
  18 #include <unistd.h>
  19 
  20 \fBchar *\fR\fBgetlogin\fR(\fBvoid\fR);
  21 .fi
  22 
  23 .LP
  24 .nf
  25 \fBchar *\fR\fBgetlogin_r\fR(\fBchar *\fR\fIname\fR, \fBint\fR \fInamelen\fR);
  26 .fi
  27 
  28 .SS "Standard conforming"
  29 .LP
  30 .nf
  31 cc [ \fIflag \fR... ] \fIfile\fR... \fB-D_POSIX_PTHREAD_SEMANTICS\fR [ \fIlibrary \fR... ]
  32 
  33 \fBint\fR \fBgetlogin_r\fR(\fBchar *\fR\fIname\fR, \fBsize_t\fR \fInamesize\fR);
  34 .fi
  35 
  36 .SH DESCRIPTION
  37 .sp
  38 .LP
  39 The \fBgetlogin()\fR function returns a pointer to the login name as found in
  40 \fB/var/adm/utmpx\fR. It can be used in conjunction with \fBgetpwnam\fR(3C) to
  41 locate the correct password file entry when the same user \fBID\fR is shared by
  42 several login names.
  43 .sp
  44 .LP






















  45 If \fBgetlogin()\fR is called within a process that is not attached to a
  46 terminal, it returns a null pointer. The correct procedure for determining the
  47 login name is to call \fBcuserid\fR(3C), or to call \fBgetlogin()\fR and if it
  48 fails to call \fBgetpwuid\fR(3C).
  49 .sp
  50 .LP
  51 The \fBgetlogin_r()\fR function has the same functionality as \fBgetlogin()\fR
  52 except that the caller must supply a buffer \fIname\fR with length
  53 \fInamelen\fR to store the result.  The \fIname\fR buffer must be at least
  54 \fB_POSIX_LOGIN_NAME_MAX\fR bytes in size (defined in <\fBlimits.h\fR>). The
  55 POSIX version (see \fBstandards\fR(5)) of \fBgetlogin_r()\fR takes a
  56 \fInamesize\fR parameter of type \fBsize_t\fR.
  57 .SH RETURN VALUES
  58 .sp
  59 .LP
  60 Upon successful completion, \fBgetlogin()\fR returns a pointer to the login
  61 name or a null pointer if the user's login name cannot be found.  Otherwise it
  62 returns a null pointer and sets \fBerrno\fR to indicate the error.
  63 .sp
  64 .LP
  65 The standard-conforming \fBgetlogin_r()\fR returns \fB0\fR if successful, or
  66 the error number upon failure.
  67 .SH ERRORS
  68 .sp
  69 .LP
  70 The \fBgetlogin_r()\fR function will fail if:
  71 .sp
  72 .ne 2
  73 .na
  74 \fB\fBERANGE\fR\fR


 134 .LP
 135 The return value of \fBgetlogin()\fR points to thread-specific data whose
 136 content is overwritten on each call by the same thread.
 137 .sp
 138 .LP
 139 Three names associated with the current process can be determined:
 140 \fBgetpwuid(\fR\fBgeteuid()\fR\fB)\fR returns the name associated with the
 141 effective user ID of the process; \fBgetlogin()\fR returns the name associated
 142 with the current login activity; and \fBgetpwuid(\fR\fBgetuid()\fR\fB)\fR
 143 returns the name associated with the real user ID of the process.
 144 .SH FILES
 145 .sp
 146 .ne 2
 147 .na
 148 \fB\fB/var/adm/utmpx\fR\fR
 149 .ad
 150 .RS 18n
 151 user access and administration information
 152 .RE
 153 


















 154 .SH ATTRIBUTES
 155 .sp
 156 .LP
 157 See \fBattributes\fR(5) for descriptions of the following attributes:
 158 .sp
 159 
 160 .sp
 161 .TS
 162 box;
 163 c | c
 164 l | l .
 165 ATTRIBUTE TYPE  ATTRIBUTE VALUE
 166 _
 167 Interface Stability     Standard
 168 _
 169 MT-Level        See below.
 170 .TE
 171 
 172 .SH SEE ALSO
 173 .sp
   1 '\" te
   2 .\" Copyright (c) 2013 Gary Mills
   3 .\" Copyright (c) 2004 Sun Microsystems, Inc.  All Rights Reserved.
   4 .\" Copyright 1989 AT&T
   5 .\" Portions Copyright (c) 1992, X/Open Company Limited.  All Rights Reserved.
   6 .\" 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 .\" http://www.opengroup.org/bookstore/.
   8 .\" 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 http://www.opengroup.org/unix/online.html.
   9 .\"  This notice shall appear on any product containing this material.
  10 .\" 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.
  11 .\" You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE or http://www.opensolaris.org/os/licensing.  See the License for the specific language governing permissions and limitations under the License.
  12 .\" When distributing Covered Code, include this CDDL HEADER in each file and include the License file at usr/src/OPENSOLARIS.LICENSE.  If applicable, add the following below this CDDL HEADER, with the fields enclosed by brackets "[]" replaced with your own identifying information: Portions Copyright [yyyy] [name of copyright owner]
  13 .TH GETLOGIN 3C "May 25, 2013"
  14 .SH NAME
  15 getlogin, getlogin_r \- get login name
  16 .SH SYNOPSIS
  17 .LP
  18 .nf
  19 #include <unistd.h>
  20 
  21 \fBchar *\fR\fBgetlogin\fR(\fBvoid\fR);
  22 .fi
  23 
  24 .LP
  25 .nf
  26 \fBchar *\fR\fBgetlogin_r\fR(\fBchar *\fR\fIname\fR, \fBint\fR \fInamelen\fR);
  27 .fi
  28 
  29 .SS "Standard conforming"
  30 .LP
  31 .nf
  32 cc [ \fIflag \fR... ] \fIfile\fR... \fB-D_POSIX_PTHREAD_SEMANTICS\fR [ \fIlibrary \fR... ]
  33 
  34 \fBint\fR \fBgetlogin_r\fR(\fBchar *\fR\fIname\fR, \fBsize_t\fR \fInamesize\fR);
  35 .fi
  36 
  37 .SH DESCRIPTION
  38 .sp
  39 .LP
  40 The \fBgetlogin()\fR function returns a pointer to the login name as found in
  41 \fB/var/adm/utmpx\fR. It can be used in conjunction with \fBgetpwnam\fR(3C) to
  42 locate the correct password file entry when the same user \fBID\fR is shared by
  43 several login names.
  44 .sp
  45 .LP
  46 The login name plus the terminating null byte can be up to 33 characters
  47 in length.
  48 Newly-compiled programs should use the \fBLOGIN_NAME_MAX\fR symbol,
  49 defined in <\fBlimits.h\fR>, to size the buffer.
  50 Older programs that call \fBgetlogin()\fR  expect only the legacy
  51 9-character length.
  52 These automatically link to a version of the \fBgetlogin()\fR functions that
  53 truncates longer login names.
  54 It's also possible to compile new programs that link to truncating versions
  55 of these functions by defining \fB__USE_LEGACY_LOGNAME__\fR in the
  56 compile environment.
  57 .sp
  58 .LP
  59 Some older programs will correctly handle long login names returned
  60 by the \fBgetlogin()\fR function.
  61 For this case, the user compatibility library
  62 \fB/usr/lib/getloginx.so.1\fR redirects to a version of the \fBgetlogin()\fR
  63 function that returns the long name.
  64 This library should be added to such an application
  65 at runtime using \fBLD_PRELOAD\fR.
  66 .sp
  67 .LP
  68 If \fBgetlogin()\fR is called within a process that is not attached to a
  69 terminal, it returns a null pointer. The correct procedure for determining the
  70 login name is to call \fBcuserid\fR(3C), or to call \fBgetlogin()\fR and if it
  71 fails to call \fBgetpwuid\fR(3C).
  72 .sp
  73 .LP
  74 The \fBgetlogin_r()\fR function has the same functionality as \fBgetlogin()\fR
  75 except that the caller must supply a buffer \fIname\fR with length
  76 \fInamelen\fR to store the result.  The \fIname\fR buffer must be at least
  77 \fBLOGIN_NAME_MAX\fR bytes in size (defined in <\fBlimits.h\fR>). The
  78 POSIX version (see \fBstandards\fR(5)) of \fBgetlogin_r()\fR takes a
  79 \fInamesize\fR parameter of type \fBsize_t\fR.
  80 .SH RETURN VALUES
  81 .sp
  82 .LP
  83 Upon successful completion, \fBgetlogin()\fR returns a pointer to the login
  84 name or a null pointer if the user's login name cannot be found.  Otherwise it
  85 returns a null pointer and sets \fBerrno\fR to indicate the error.
  86 .sp
  87 .LP
  88 The standard-conforming \fBgetlogin_r()\fR returns \fB0\fR if successful, or
  89 the error number upon failure.
  90 .SH ERRORS
  91 .sp
  92 .LP
  93 The \fBgetlogin_r()\fR function will fail if:
  94 .sp
  95 .ne 2
  96 .na
  97 \fB\fBERANGE\fR\fR


 157 .LP
 158 The return value of \fBgetlogin()\fR points to thread-specific data whose
 159 content is overwritten on each call by the same thread.
 160 .sp
 161 .LP
 162 Three names associated with the current process can be determined:
 163 \fBgetpwuid(\fR\fBgeteuid()\fR\fB)\fR returns the name associated with the
 164 effective user ID of the process; \fBgetlogin()\fR returns the name associated
 165 with the current login activity; and \fBgetpwuid(\fR\fBgetuid()\fR\fB)\fR
 166 returns the name associated with the real user ID of the process.
 167 .SH FILES
 168 .sp
 169 .ne 2
 170 .na
 171 \fB\fB/var/adm/utmpx\fR\fR
 172 .ad
 173 .RS 18n
 174 user access and administration information
 175 .RE
 176 
 177 .sp
 178 .ne 2
 179 .na
 180 \fB\fB/usr/lib/getloginx.so.1\fR\fR
 181 .ad
 182 .RS 18n
 183 A compatibility library that returns long login names to older applications.
 184 .RE
 185 
 186 .sp
 187 .ne 2
 188 .na
 189 \fB\fB/usr/lib/64/getloginx.so.1\fR\fR
 190 .ad
 191 .RS 18n
 192 A 64-bit compatibility library to return long login names.
 193 .RE
 194 
 195 .SH ATTRIBUTES
 196 .sp
 197 .LP
 198 See \fBattributes\fR(5) for descriptions of the following attributes:
 199 .sp
 200 
 201 .sp
 202 .TS
 203 box;
 204 c | c
 205 l | l .
 206 ATTRIBUTE TYPE  ATTRIBUTE VALUE
 207 _
 208 Interface Stability     Standard
 209 _
 210 MT-Level        See below.
 211 .TE
 212 
 213 .SH SEE ALSO
 214 .sp