granicus.if.org Git - shadow/blob - man/useradd.8.xml

   1 <?xml version="1.0" encoding="UTF-8"?>
   2 <!--
   3    Copyright (c) 1991 - 1994, Julianne Frances Haugh
   4    Copyright (c) 2007 - 2009, Nicolas François
   5    All rights reserved.
   6
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   8    modification, are permitted provided that the following conditions
   9    are met:
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  14       documentation and/or other materials provided with the distribution.
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  16       endorse or promote products derived from this software without
  17       specific prior written permission.
  18
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  20    ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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  31 <!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook V4.5//EN"
  32   "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd" [
  33 <!ENTITY CREATE_HOME           SYSTEM "login.defs.d/CREATE_HOME.xml">
  34 <!ENTITY GID_MAX               SYSTEM "login.defs.d/GID_MAX.xml">
  35 <!ENTITY MAIL_DIR              SYSTEM "login.defs.d/MAIL_DIR.xml">
  36 <!ENTITY MAX_MEMBERS_PER_GROUP SYSTEM "login.defs.d/MAX_MEMBERS_PER_GROUP.xml">
  37 <!ENTITY PASS_MAX_DAYS         SYSTEM "login.defs.d/PASS_MAX_DAYS.xml">
  38 <!ENTITY PASS_MIN_DAYS         SYSTEM "login.defs.d/PASS_MIN_DAYS.xml">
  39 <!ENTITY PASS_WARN_AGE         SYSTEM "login.defs.d/PASS_WARN_AGE.xml">
  40 <!ENTITY SYS_GID_MAX           SYSTEM "login.defs.d/SYS_GID_MAX.xml">
  41 <!ENTITY SYS_UID_MAX           SYSTEM "login.defs.d/SYS_UID_MAX.xml">
  42 <!ENTITY UID_MAX               SYSTEM "login.defs.d/UID_MAX.xml">
  43 <!ENTITY UMASK                 SYSTEM "login.defs.d/UMASK.xml">
  44 <!ENTITY TCB_AUTH_GROUP        SYSTEM "login.defs.d/TCB_AUTH_GROUP.xml">
  45 <!ENTITY TCB_SYMLINKS          SYSTEM "login.defs.d/TCB_SYMLINKS.xml">
  46 <!ENTITY USE_TCB               SYSTEM "login.defs.d/USE_TCB.xml">
  47 <!ENTITY USERGROUPS_ENAB       SYSTEM "login.defs.d/USERGROUPS_ENAB.xml">
  48 ]>
  49 <refentry id='useradd.8'>
  50   <!--  $Id$ -->
  51   <refmeta>
  52     <refentrytitle>useradd</refentrytitle>
  53     <manvolnum>8</manvolnum>
  54     <refmiscinfo class="sectdesc">System Management Commands</refmiscinfo>
  55   </refmeta>
  56   <refnamediv id='name'>
  57     <refname>useradd</refname>
  58     <refpurpose>create a new user or update default new user information</refpurpose>
  59   </refnamediv>
  60   <refsynopsisdiv id='synopsis'>
  61     <cmdsynopsis>
  62       <command>useradd</command>
  63       <arg choice='opt'>
  64         <replaceable>options</replaceable>
  65       </arg>
  66       <arg choice='plain'><replaceable>LOGIN</replaceable></arg>
  67     </cmdsynopsis>
  68     <cmdsynopsis>
  69       <command>useradd</command>
  70       <arg choice='plain'>-D </arg>
  71     </cmdsynopsis>
  72     <cmdsynopsis>
  73       <command>useradd</command>
  74       <arg choice='plain'>-D </arg>
  75       <arg choice='opt'>
  76         <replaceable>options</replaceable>
  77       </arg>
  78     </cmdsynopsis>
  79   </refsynopsisdiv>
  80
  81   <refsect1 id='description'>
  82     <title>DESCRIPTION</title>
  83       <para>
  84         When invoked without the <option>-D</option> option, the
  85         <command>useradd</command> command creates a new user account using
  86         the values specified on the command line plus the default values from
  87         the system. Depending on command line options, the
  88         <command>useradd</command> command
  89         will update system files and may also create the new user's home
  90         directory and copy initial files.
  91       </para>
  92       <para>
  93         By default, a group will also be created for the new user (see
  94         <option>-g</option>, <option>-N</option>, <option>-U</option>, and
  95         <option>USERGROUPS_ENAB</option>).
  96       </para>
  97   </refsect1>
  98
  99   <refsect1 id='options'>
 100     <title>OPTIONS</title>
 101     <para>The options which apply to the <command>useradd</command> command are:
 102     </para>
 103     <variablelist remap='IP'>
 104       <varlistentry>
 105         <term>
 106           <option>-b</option>, <option>--base-dir</option>
 107           <replaceable>BASE_DIR</replaceable>
 108         </term>
 109         <listitem>
 110           <para>
 111             The default base directory for the system if <option>-d</option>
 112             <replaceable>HOME_DIR</replaceable> is not specified.
 113             <replaceable>BASE_DIR</replaceable> is
 114             concatenated with the account name to define the home directory.
 115             If the <option>-m</option> option is not used,
 116             <replaceable>BASE_DIR</replaceable> must exist.
 117           </para>
 118           <para>
 119             If this option is not specified, <command>useradd</command>
 120             will use the base directory specified by the
 121             <option>HOME</option> variable in
 122             <filename>/etc/default/useradd</filename>, or
 123             <filename>/home</filename> by default.
 124           </para>
 125         </listitem>
 126       </varlistentry>
 127       <varlistentry>
 128         <term>
 129           <option>-c</option>, <option>--comment</option>
 130           <replaceable>COMMENT</replaceable>
 131         </term>
 132         <listitem>
 133           <para>
 134             Any text string. It is generally a short description of the
 135             login, and is currently used as the field for the user's full
 136             name.
 137           </para>
 138         </listitem>
 139       </varlistentry>
 140       <varlistentry>
 141         <term>
 142           <option>-d</option>, <option>--home</option>
 143           <replaceable>HOME_DIR</replaceable>
 144         </term>
 145         <listitem>
 146           <para>
 147             The new user will be created using
 148             <replaceable>HOME_DIR</replaceable> as the value for the user's
 149             login directory. The default is to append the
 150             <replaceable>LOGIN</replaceable> name to
 151             <replaceable>BASE_DIR</replaceable> and use that as the login
 152             directory name. The directory <replaceable>HOME_DIR</replaceable>
 153             does not have to exist but will not be created if it is missing.
 154           </para>
 155         </listitem>
 156       </varlistentry>
 157       <varlistentry>
 158         <term>
 159           <option>-D</option>, <option>--defaults</option>
 160         </term>
 161         <listitem>
 162           <para>
 163             See below, the subsection "Changing the default values".
 164           </para>
 165         </listitem>
 166       </varlistentry>
 167       <varlistentry>
 168         <term>
 169           <option>-e</option>, <option>--expiredate</option>
 170           <replaceable>EXPIRE_DATE</replaceable>
 171         </term>
 172         <listitem>
 173           <para>
 174             The date on which the user account will be disabled. The date is
 175             specified in the format <emphasis remap='I'>YYYY-MM-DD</emphasis>.
 176           </para>
 177           <para>
 178             If not specified, <command>useradd</command> will use the
 179             default expiry date specified by the <option>EXPIRE</option>
 180             variable in <filename>/etc/default/useradd</filename>, or
 181             an empty string (no expiry) by default.
 182           </para>
 183         </listitem>
 184       </varlistentry>
 185       <varlistentry>
 186         <term>
 187           <option>-f</option>, <option>--inactive</option>
 188           <replaceable>INACTIVE</replaceable>
 189         </term>
 190         <listitem>
 191           <para>
 192             The number of days after a password expires until the account is
 193             permanently disabled. A value of 0 disables the account as soon
 194             as the password has expired, and a value of -1 disables the
 195             feature.
 196           </para>
 197           <para>
 198             If not specified, <command>useradd</command> will use the
 199             default inactivity period specified by the
 200             <option>INACTIVE</option> variable in
 201             <filename>/etc/default/useradd</filename>, or -1 by default.
 202           </para>
 203         </listitem>
 204       </varlistentry>
 205       <varlistentry>
 206         <term>
 207           <option>-g</option>, <option>--gid</option>
 208           <replaceable>GROUP</replaceable>
 209         </term>
 210         <listitem>
 211           <para>
 212             The group name or number of the user's initial login group. The
 213             group name must exist. A group number must refer to an already
 214             existing group.
 215           </para>
 216           <para>
 217             If not specified, the behavior of <command>useradd</command>
 218             will depend on the <option>USERGROUPS_ENAB</option> variable
 219             in <filename>/etc/login.defs</filename>. If this variable is
 220             set to <replaceable>yes</replaceable> (or
 221             <option>-U/--user-group</option> is specified on the command
 222             line), a group will be created for the user, with the same
 223             name as her loginname. If the variable is set to
 224             <replaceable>no</replaceable> (or
 225             <option>-N/--no-user-group</option> is specified on the
 226             command line), useradd will set the primary group of the new
 227             user to the value specified by the <option>GROUP</option>
 228             variable in <filename>/etc/default/useradd</filename>, or
 229             100 by default.
 230           </para>
 231         </listitem>
 232       </varlistentry>
 233       <varlistentry>
 234         <term>
 235           <option>-G</option>, <option>--groups</option>
 236           <replaceable>GROUP1</replaceable>[<emphasis remap='I'>,GROUP2,...</emphasis>[<emphasis remap='I'>,GROUPN</emphasis>]]]
 237         </term>
 238         <listitem>
 239           <para>
 240             A list of supplementary groups which the user is also a member
 241             of. Each group is separated from the next by a comma, with no
 242             intervening whitespace. The groups are subject to the same
 243             restrictions as the group given with the <option>-g</option>
 244             option. The default is for the user to belong only to the
 245             initial group.
 246           </para>
 247         </listitem>
 248       </varlistentry>
 249       <varlistentry>
 250         <term><option>-h</option>, <option>--help</option></term>
 251         <listitem>
 252           <para>Display help message and exit.</para>
 253         </listitem>
 254       </varlistentry>
 255       <varlistentry>
 256         <term>
 257           <option>-k</option>, <option>--skel</option>
 258           <replaceable>SKEL_DIR</replaceable>
 259         </term>
 260         <listitem>
 261           <para>
 262             The skeleton directory, which contains files and directories
 263             to be copied in the user's home directory, when the home
 264             directory is created by <command>useradd</command>.
 265           </para>
 266           <para>
 267             This option is only valid if the <option>-m</option> (or
 268             <option>--create-home</option>) option is specified.
 269           </para>
 270           <para>
 271             If this option is not set, the skeleton directory is defined
 272             by the <option>SKEL</option> variable in
 273             <filename>/etc/default/useradd</filename> or, by default,
 274             <filename>/etc/skel</filename>.
 275           </para>
 276           <para>
 277             If possible, the ACLs and extended attributes are copied.
 278           </para>
 279         </listitem>
 280       </varlistentry>
 281       <varlistentry>
 282         <term>
 283           <option>-K</option>, <option>--key</option>
 284           <replaceable>KEY</replaceable>=<replaceable>VALUE</replaceable>
 285         </term>
 286         <listitem>
 287           <para>
 288             Overrides <filename>/etc/login.defs</filename> defaults
 289             (<option>UID_MIN</option>, <option>UID_MAX</option>,
 290             <option>UMASK</option>, <option>PASS_MAX_DAYS</option>
 291             and others).
 292           <para>
 293           </para>
 294             Example: <option>-K </option><replaceable>PASS_MAX_DAYS</replaceable>=<replaceable>-1</replaceable>
 295             can be used when creating system account to turn off password
 296             ageing, even though system account has no password at all.
 297             Multiple <option>-K</option> options can be specified, e.g.:
 298             <option>-K </option>
 299             <replaceable>UID_MIN</replaceable>=<replaceable>100</replaceable>
 300             <option>-K </option>
 301             <replaceable>UID_MAX</replaceable>=<replaceable>499</replaceable>
 302           </para>
 303           <!--para>
 304             Note: <option>-K </option>
 305             <replaceable>UID_MIN</replaceable>=<replaceable>10</replaceable>,<replaceable>UID_MAX</replaceable>=<replaceable>499</replaceable>
 306             doesn't work yet.
 307           </para-->
 308         </listitem>
 309       </varlistentry>
 310       <varlistentry>
 311         <term><option>-l</option>, <option>--no-log-init</option></term>
 312         <listitem>
 313           <para>
 314             Do not add the user to the lastlog and faillog databases.
 315           </para>
 316           <para>
 317             By default, the user's entries in the lastlog and faillog
 318             databases are resetted to avoid reusing the entry from a previously
 319             deleted user.
 320           </para>
 321         </listitem>
 322       </varlistentry>
 323       <varlistentry>
 324         <term>
 325           <option>-m</option>, <option>--create-home</option>
 326         </term>
 327         <listitem>
 328           <para>
 329             Create the user's home directory if it does not exist.
 330             The files and directories contained in the skeleton directory
 331             (which can be defined with the <option>-k</option> option)
 332             will be copied to the home directory.
 333           </para>
 334           <para>
 335             By default, if this option is not specified and
 336             <option>CREATE_HOME</option> is not enabled, no home
 337             directories are created.
 338           </para>
 339         </listitem>
 340       </varlistentry>
 341       <varlistentry>
 342         <term>
 343           <option>-M</option>
 344         </term>
 345         <listitem>
 346           <para>
 347             Do no create the user's home directory, even if the system
 348             wide setting from <filename>/etc/login.defs</filename>
 349             (<option>CREATE_HOME</option>) is set to
 350             <replaceable>yes</replaceable>.
 351           </para>
 352         </listitem>
 353       </varlistentry>
 354       <varlistentry>
 355         <term>
 356           <option>-N</option>, <option>--no-user-group</option>
 357         </term>
 358         <listitem>
 359           <para>
 360             Do not create a group with the same name as the user, but
 361             add the user to the group specified by the <option>-g</option>
 362             option or by the <option>GROUP</option> variable in
 363             <filename>/etc/default/useradd</filename>.
 364           </para>
 365           <para>
 366             The default behavior (if the <option>-g</option>,
 367             <option>-N</option>, and <option>-U</option> options are not
 368             specified) is defined by the <option>USERGROUPS_ENAB</option>
 369             variable in <filename>/etc/login.defs</filename>.
 370           </para>
 371         </listitem>
 372       </varlistentry>
 373       <varlistentry>
 374         <term>
 375           <option>-o</option>, <option>--non-unique</option>
 376         </term>
 377         <listitem>
 378           <para>Allow the creation of a user account with a duplicate (non-unique) UID.</para>
 379           <para>
 380             This option is only valid in combination with the
 381             <option>-u</option> option.
 382           </para>
 383         </listitem>
 384       </varlistentry>
 385       <varlistentry>
 386         <term>
 387           <option>-p</option>, <option>--password</option>
 388           <replaceable>PASSWORD</replaceable>
 389         </term>
 390         <listitem>
 391           <para>
 392             The encrypted password, as returned by <citerefentry>
 393             <refentrytitle>crypt</refentrytitle><manvolnum>3</manvolnum>
 394             </citerefentry>. The default is to disable the password.
 395           </para>
 396           <para>
 397             <emphasis role="bold">Note:</emphasis> This option is not
 398             recommended because the password (or encrypted password) will
 399             be visible by users listing the processes.
 400           </para>
 401           <para>
 402             You should make sure the password respects the system's
 403             password policy.
 404           </para>
 405         </listitem>
 406       </varlistentry>
 407       <varlistentry>
 408         <term>
 409           <option>-r</option>, <option>--system</option>
 410         </term>
 411         <listitem>
 412           <para>
 413             Create a system account.
 414           </para>
 415           <para>
 416             System users will be created with no aging information in
 417             <filename>/etc/shadow</filename>, and their numeric
 418             identifiers are chosen in the
 419             <option>SYS_UID_MIN</option>-<option>SYS_UID_MAX</option>
 420             range, defined in <filename>/etc/login.defs</filename>, instead of
 421             <option>UID_MIN</option>-<option>UID_MAX</option> (and their
 422             <option>GID</option> counterparts for the creation of groups).
 423           </para>
 424           <para>
 425             Note that <command>useradd</command> will not create a home
 426             directory for such an user, regardless of the default setting
 427             in <filename>/etc/login.defs</filename>
 428             (<option>CREATE_HOME</option>). You have to specify the
 429             <option>-m</option> options if you want a home directory for a
 430             system account to be created.
 431           </para>
 432         </listitem>
 433       </varlistentry>
 434       <varlistentry>
 435         <term>
 436           <option>-s</option>, <option>--shell</option>
 437           <replaceable>SHELL</replaceable>
 438         </term>
 439         <listitem>
 440           <para>
 441             The name of the user's login shell. The default is to leave this
 442             field blank, which causes the system to select the default login
 443             shell specified by the <option>SHELL</option> variable in
 444             <filename>/etc/default/useradd</filename>, or an empty string
 445             by default.
 446           </para>
 447         </listitem>
 448       </varlistentry>
 449       <varlistentry>
 450         <term>
 451           <option>-u</option>, <option>--uid</option>
 452           <replaceable>UID</replaceable>
 453         </term>
 454         <listitem>
 455           <para>
 456             The numerical value of the user's ID. This value must be unique,
 457             unless the <option>-o</option> option is used. The value must be
 458             non-negative. The default is to use the smallest ID value
 459             greater than 999 and greater than every other user. Values
 460             between 0 and 999 are typically reserved for system accounts.
 461           </para>
 462         </listitem>
 463       </varlistentry>
 464       <varlistentry>
 465         <term>
 466           <option>-U</option>, <option>--user-group</option>
 467         </term>
 468         <listitem>
 469           <para>
 470             Create a group with the same name as the user, and
 471             add the user to this group.
 472           </para>
 473           <para>
 474             The default behavior (if the <option>-g</option>,
 475             <option>-N</option>, and <option>-U</option> options are not
 476             specified) is defined by the <option>USERGROUPS_ENAB</option>
 477             variable in <filename>/etc/login.defs</filename>.
 478           </para>
 479         </listitem>
 480       </varlistentry>
 481       <varlistentry>
 482         <term>
 483           <option>-Z</option>, <option>--selinux-user</option>
 484           <replaceable>SEUSER</replaceable>
 485         </term>
 486         <listitem>
 487           <para>
 488             The SELinux user for the user's login. The default is to leave this
 489             field blank, which causes the system to select the default SELinux
 490              user.
 491           </para>
 492         </listitem>
 493       </varlistentry>
 494     </variablelist>
 495
 496     <refsect2 id='changing_the_default_values'>
 497       <title>Changing the default values</title>
 498       <para>
 499         When invoked with only the <option>-D</option> option,
 500         <command>useradd</command> will display the current default values.
 501         When invoked with <option>-D</option> plus other options,
 502         <command>useradd</command> will update the default values for the
 503         specified options. Valid default-changing options are:
 504       </para>
 505       <variablelist remap='IP'>
 506         <varlistentry>
 507           <term>
 508             <option>-b</option>, <option>--base-dir</option>
 509             <replaceable>BASE_DIR</replaceable>
 510           </term>
 511           <listitem>
 512             <para>
 513               The path prefix for a new user's home directory. The
 514               user's name will be affixed to the end of
 515               <replaceable>BASE_DIR</replaceable> to form the new user's
 516               home directory name, if the <option>-d</option> option is not used
 517               when creating a new account.
 518             </para>
 519             <para>
 520               This option sets the <option>HOME</option> variable in
 521               <filename>/etc/default/useradd</filename>.
 522             </para>
 523           </listitem>
 524         </varlistentry>
 525         <varlistentry>
 526           <term>
 527             <option>-e</option>, <option>--expiredate</option>
 528             <replaceable>EXPIRE_DATE</replaceable>
 529           </term>
 530           <listitem>
 531             <para>The date on which the user account is disabled.</para>
 532             <para>
 533               This option sets the <option>EXPIRE</option> variable in
 534               <filename>/etc/default/useradd</filename>.
 535             </para>
 536           </listitem>
 537         </varlistentry>
 538         <varlistentry>
 539           <term>
 540             <option>-f</option>, <option>--inactive</option>
 541             <replaceable>INACTIVE</replaceable>
 542           </term>
 543           <listitem>
 544             <para>
 545               The number of days after a password has expired before the
 546               account will be disabled.
 547             </para>
 548             <para>
 549               This option sets the <option>INACTIVE</option> variable in
 550               <filename>/etc/default/useradd</filename>.
 551             </para>
 552           </listitem>
 553         </varlistentry>
 554         <varlistentry>
 555           <term>
 556             <option>-g</option>, <option>--gid</option>
 557             <replaceable>GROUP</replaceable>
 558           </term>
 559           <listitem>
 560             <para>
 561               The group name or ID for a new user's initial group (when
 562               the <option>-N/--no-user-group</option> is used or when the
 563               <option>USERGROUPS_ENAB</option> variable is set to
 564               <replaceable>no</replaceable> in
 565               <filename>/etc/login.defs</filename>. The named
 566               group must exist, and a numerical group ID must have an
 567               existing entry.
 568             </para>
 569             <para>
 570               This option sets the <option>GROUP</option> variable in
 571               <filename>/etc/default/useradd</filename>.
 572             </para>
 573           </listitem>
 574         </varlistentry>
 575         <varlistentry>
 576           <term>
 577             <option>-s</option>, <option>--shell</option>
 578             <replaceable>SHELL</replaceable>
 579           </term>
 580           <listitem>
 581             <para>
 582               The name of a new user's login shell.
 583             </para>
 584             <para>
 585               This option sets the <option>SHELL</option> variable in
 586               <filename>/etc/default/useradd</filename>.
 587             </para>
 588           </listitem>
 589         </varlistentry>
 590       </variablelist>
 591
 592     </refsect2>
 593   </refsect1>
 594
 595   <refsect1 id='notes'>
 596     <title>NOTES</title>
 597     <para>The system administrator is responsible for placing the default
 598       user files in the <filename>/etc/skel/</filename> directory (or any
 599       other skeleton directory specified in
 600       <filename>/etc/default/useradd</filename> or on the command line).
 601     </para>
 602   </refsect1>
 603
 604   <refsect1 id='caveats'>
 605     <title>CAVEATS</title>
 606     <para>
 607       You may not add a user to a NIS or LDAP group. This must be
 608       performed on the corresponding server.
 609     </para>
 610
 611     <para>
 612       Similarly, if the username already exists in an external user
 613       database such as NIS or LDAP, <command>useradd</command> will deny
 614       the user account creation request.
 615     </para>
 616
 617     <para>
 618       Usernames must start with a lower case letter or an underscore,
 619       followed by lower case letters, digits, underscores, or dashes.
 620       They can end with a dollar sign.
 621       In regular expression terms: [a-z_][a-z0-9_-]*[$]?
 622     </para>
 623     <para>
 624       Usernames may only be up to 32 characters long.
 625     </para>
 626   </refsect1>
 627
 628   <refsect1 id='configuration'>
 629     <title>CONFIGURATION</title>
 630     <para>
 631       The following configuration variables in
 632       <filename>/etc/login.defs</filename> change the behavior of this
 633       tool:
 634     </para>
 635     <variablelist>
 636       &CREATE_HOME;
 637       &GID_MAX; <!-- documents also GID_MIN -->
 638       &MAIL_DIR;
 639       &MAX_MEMBERS_PER_GROUP;
 640       &PASS_MAX_DAYS;
 641       &PASS_MIN_DAYS;
 642       &PASS_WARN_AGE;
 643       &SYS_GID_MAX; <!-- documents also SYS_GID_MIN -->
 644       &SYS_UID_MAX; <!-- documents also SYS_UID_MIN -->
 645       &TCB_AUTH_GROUP;
 646       &TCB_SYMLINKS;
 647       &UID_MAX; <!-- documents also UID_MIN -->
 648       &UMASK;
 649       &USE_TCB;
 650       &USERGROUPS_ENAB;
 651     </variablelist>
 652   </refsect1>
 653
 654   <refsect1 id='files'>
 655     <title>FILES</title>
 656     <variablelist>
 657       <varlistentry>
 658         <term><filename>/etc/passwd</filename></term>
 659         <listitem>
 660           <para>User account information.</para>
 661         </listitem>
 662       </varlistentry>
 663       <varlistentry>
 664         <term><filename>/etc/shadow</filename></term>
 665         <listitem>
 666           <para>Secure user account information.</para>
 667         </listitem>
 668       </varlistentry>
 669       <varlistentry>
 670         <term><filename>/etc/group</filename></term>
 671         <listitem>
 672           <para>Group account information.</para>
 673         </listitem>
 674       </varlistentry>
 675       <varlistentry condition="gshadow">
 676         <term><filename>/etc/gshadow</filename></term>
 677         <listitem>
 678           <para>Secure group account information.</para>
 679         </listitem>
 680       </varlistentry>
 681       <varlistentry>
 682         <term><filename>/etc/default/useradd</filename></term>
 683         <listitem>
 684           <para>Default values for account creation.</para>
 685         </listitem>
 686       </varlistentry>
 687       <varlistentry>
 688         <term><filename>/etc/skel/</filename></term>
 689         <listitem>
 690           <para>Directory containing default files.</para>
 691         </listitem>
 692       </varlistentry>
 693       <varlistentry>
 694         <term><filename>/etc/login.defs</filename></term>
 695         <listitem>
 696           <para>Shadow password suite configuration.</para>
 697         </listitem>
 698       </varlistentry>
 699     </variablelist>
 700   </refsect1>
 701
 702   <refsect1 id='exit_values'>
 703     <title>EXIT VALUES</title>
 704     <para>
 705       The <command>useradd</command> command exits with the following values:
 706       <variablelist>
 707         <varlistentry>
 708           <term><replaceable>0</replaceable></term>
 709           <listitem>
 710             <para>success</para>
 711           </listitem>
 712         </varlistentry>
 713         <varlistentry>
 714           <term><replaceable>1</replaceable></term>
 715           <listitem>
 716             <para>can't update password file</para>
 717           </listitem>
 718         </varlistentry>
 719         <varlistentry>
 720           <term><replaceable>2</replaceable></term>
 721           <listitem>
 722             <para>invalid command syntax</para>
 723           </listitem>
 724         </varlistentry>
 725         <varlistentry>
 726           <term><replaceable>3</replaceable></term>
 727           <listitem>
 728             <para>invalid argument to option</para>
 729           </listitem>
 730         </varlistentry>
 731         <varlistentry>
 732           <term><replaceable>4</replaceable></term>
 733           <listitem>
 734             <para>UID already in use (and no <option>-o</option>)</para>
 735           </listitem>
 736         </varlistentry>
 737         <varlistentry>
 738           <term><replaceable>6</replaceable></term>
 739           <listitem>
 740             <para>specified group doesn't exist</para>
 741           </listitem>
 742         </varlistentry>
 743         <varlistentry>
 744           <term><replaceable>9</replaceable></term>
 745           <listitem>
 746             <para>username already in use</para>
 747           </listitem>
 748         </varlistentry>
 749         <varlistentry>
 750           <term><replaceable>10</replaceable></term>
 751           <listitem>
 752             <para>can't update group file</para>
 753           </listitem>
 754         </varlistentry>
 755         <varlistentry>
 756           <term><replaceable>12</replaceable></term>
 757           <listitem>
 758             <para>can't create home directory</para>
 759           </listitem>
 760         </varlistentry>
 761         <varlistentry>
 762           <term><replaceable>13</replaceable></term>
 763           <listitem>
 764             <para>can't create mail spool</para>
 765           </listitem>
 766         </varlistentry>
 767       </variablelist>
 768     </para>
 769   </refsect1>
 770
 771   <refsect1 id='see_also'>
 772     <title>SEE ALSO</title>
 773     <para>
 774       <citerefentry>
 775         <refentrytitle>chfn</refentrytitle><manvolnum>1</manvolnum>
 776       </citerefentry>,
 777       <citerefentry>
 778         <refentrytitle>chsh</refentrytitle><manvolnum>1</manvolnum>
 779       </citerefentry>,
 780       <citerefentry>
 781         <refentrytitle>passwd</refentrytitle><manvolnum>1</manvolnum>
 782       </citerefentry>,
 783       <citerefentry>
 784         <refentrytitle>crypt</refentrytitle><manvolnum>3</manvolnum>
 785       </citerefentry>,
 786       <citerefentry>
 787         <refentrytitle>groupadd</refentrytitle><manvolnum>8</manvolnum>
 788       </citerefentry>,
 789       <citerefentry>
 790         <refentrytitle>groupdel</refentrytitle><manvolnum>8</manvolnum>
 791       </citerefentry>,
 792       <citerefentry>
 793         <refentrytitle>groupmod</refentrytitle><manvolnum>8</manvolnum>
 794       </citerefentry>,
 795       <citerefentry>
 796         <refentrytitle>login.defs</refentrytitle><manvolnum>5</manvolnum>
 797       </citerefentry>,
 798       <citerefentry>
 799         <refentrytitle>newusers</refentrytitle><manvolnum>8</manvolnum>
 800       </citerefentry>,
 801       <citerefentry>
 802         <refentrytitle>userdel</refentrytitle><manvolnum>8</manvolnum>
 803       </citerefentry>,
 804       <citerefentry>
 805         <refentrytitle>usermod</refentrytitle><manvolnum>8</manvolnum>
 806       </citerefentry>.
 807     </para>
 808   </refsect1>
 809 </refentry>