adduser.conf(5)


NAME

   /etc/adduser.conf - configuration file for adduser(8) and addgroup(8).

DESCRIPTION

   The   file   /etc/adduser.conf   contains  defaults  for  the  programs
   adduser(8) , addgroup(8) , deluser(8) and delgroup(8).  Each line holds
   a  single  value  pair  in  the  form option = value.  Double or single
   quotes are allowed around the value, as is whitespace around the equals
   sign.  Comment lines must have a hash sign (#) in the first column.

   The valid configuration options are:

   DSHELL The  login  shell  to  be  used  for all new users.  Defaults to
          /bin/bash.

   DHOME  The directory in which new home directories should  be  created.
          Defaults to /home.

   GROUPHOMES
          If  this  is set to yes, the home directories will be created as
          /home/[groupname]/user.  Defaults to no.

   LETTERHOMES
          If this is set to yes, then the home  directories  created  will
          have  an  extra  directory inserted which is the first letter of
          the loginname.  For example: /home/u/user.  Defaults to no.

   SKEL   The directory  from  which  skeletal  user  configuration  files
          should be copied.  Defaults to /etc/skel.

   FIRST_SYSTEM_UID and LAST_SYSTEM_UID
          specify an inclusive range of UIDs from which system UIDs can be
          dynamically allocated. Default to 100 - 999.  Please  note  that
          system  software, such as the users allocated by the base-passwd
          package, may assume that UIDs less than 100 are unallocated.

   FIRST_UID and LAST_UID
          specify an inclusive range of UIDs from which normal user's UIDs
          can be dynamically allocated. Default to 1000 - 29999.

   FIRST_SYSTEM_GID and LAST_SYSTEM_GID
          specify an inclusive range of GIDs from which system GIDs can be
          dynamically allocated.  Default to 100 - 999.

   FIRST_GID and LAST_GID
          specify an inclusive range of GIDs  from  which  normal  group's
          GIDs can be dynamically allocated. Default to 1000 - 29999.

   USERGROUPS
          If  this  is  set  to  yes, then each created user will be given
          their own group to use.  If this is no, then each  created  user
          will  be placed in the group whose GID is USERS_GID (see below).
          The default is yes.

   USERS_GID
          If USERGROUPS is no, then USERS_GID is  the  GID  given  to  all
          newly-created users.  The default value is 100.

   DIR_MODE
          If  set to a valid value (e.g. 0755 or 755), directories created
          will have the specified permissions as umask. Otherwise 0755  is
          used as default.

   SETGID_HOME
          If  this  is  set  to  yes, then home directories for users with
          their own group ( USERGROUPS=yes ) will have the setgid bit set.
          This  was  the  default  setting  for  adduser versions << 3.13.
          Unfortunately it has some bad side effects, so we no  longer  do
          this  per  default.  If  you  want it nevertheless you can still
          activate it here.

   QUOTAUSER
          If set to a nonempty value, new users will  have  quotas  copied
          from that user.  The default is empty.

   NAME_REGEX
          User   and   group   names  are  checked  against  this  regular
          expression. If the name doesn't  match  this  regexp,  user  and
          group  creation  in adduser is refused unless --force-badname is
          set. With --force-badname set, only weak checks  are  performed.
          The  default  is  the most conservative ^[a-z][-a-z0-9]*$.  When
          --system is specified, NAME_REGEX_SYSTEM is used instead.

   NAME_REGEX_SYSTEM
          Names  of  system  users  are  checked  against   this   regular
          expression.   If --system is supplied and the name doesn't match
          this regexp, user creation in adduser is refused unless --force-
          badname  is  set. With --force-badname set, only weak checks are
          performed. The default is as for the default NAME_REGEX but also
          allowing uppercase letters.

   SKEL_IGNORE_REGEX
          Files  in  /etc/skel/  are  checked  against this regex, and not
          copied to the newly created home directory if they match.   This
          is  by default set to the regular expression matching files left
          over from unmerged config files (dpkg-(old|new|dist)).

   ADD_EXTRA_GROUPS
          Setting this to something other than 0 (the default) will  cause
          adduser  to  add  newly  created non-system users to the list of
          groups defined by EXTRA_GROUPS (below).

   EXTRA_GROUPS
          This is the list of groups that new  non-system  users  will  be
          added  to.  By default, this list is 'dialout cdrom floppy audio
          video plugdev users games'

NOTES

   VALID NAMES
          adduser and addgroup enforce conformity to IEEE Std 1003.1-2001,
          which  allows  only  the following characters to appear in group
          and user names: letters, digits, underscores, periods, at  signs
          (@)  and dashes. The name may no start with a dash. The "$" sign
          is allowed at the end of usernames (to conform to samba).

          An additional  check  can  be  adjusted  via  the  configuration
          parameter NAME_REGEX to enforce a local policy.

FILES

   /etc/adduser.conf

SEE ALSO

   adduser(8), addgroup(8), deluser(8), delgroup(8), deluser.conf(5)





Opportunity


Personal Opportunity - Free software gives you access to billions of dollars of software at no cost. Use this software for your business, personal use or to develop a profitable skill. Access to source code provides access to a level of capabilities/information that companies protect though copyrights. Open source is a core component of the Internet and it is available to you. Leverage the billions of dollars in resources and capabilities to build a career, establish a business or change the world. The potential is endless for those who understand the opportunity.

Business Opportunity - Goldman Sachs, IBM and countless large corporations are leveraging open source to reduce costs, develop products and increase their bottom lines. Learn what these companies know about open source and how open source can give you the advantage.





Free Software


Free Software provides computer programs and capabilities at no cost but more importantly, it provides the freedom to run, edit, contribute to, and share the software. The importance of free software is a matter of access, not price. Software at no cost is a benefit but ownership rights to the software and source code is far more significant.


Free Office Software - The Libre Office suite provides top desktop productivity tools for free. This includes, a word processor, spreadsheet, presentation engine, drawing and flowcharting, database and math applications. Libre Office is available for Linux or Windows.





Free Books


The Free Books Library is a collection of thousands of the most popular public domain books in an online readable format. The collection includes great classical literature and more recent works where the U.S. copyright has expired. These books are yours to read and use without restrictions.


Source Code - Want to change a program or know how it works? Open Source provides the source code for its programs so that anyone can use, modify or learn how to write those programs themselves. Visit the GNU source code repositories to download the source.





Education


Study at Harvard, Stanford or MIT - Open edX provides free online courses from Harvard, MIT, Columbia, UC Berkeley and other top Universities. Hundreds of courses for almost all major subjects and course levels. Open edx also offers some paid courses and selected certifications.


Linux Manual Pages - A man or manual page is a form of software documentation found on Linux/Unix operating systems. Topics covered include computer programs (including library and system calls), formal standards and conventions, and even abstract concepts.