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Linux in a Nutshell, Fourth Edition
book

Linux in a Nutshell, Fourth Edition

by Ellen Siever, Stephen Figgins, Aaron Weber
June 2003
Beginner to intermediate
944 pages
43h 1m
English
O'Reilly Media, Inc.
Content preview from Linux in a Nutshell, Fourth Edition

Name

useradd

Synopsis

                  useradd [options] [user]

System administration command. Create new user accounts or update default account information. Unless invoked with the -D option, user must be given. useradd will create new entries in system files. Home directories and initial files may also be created as needed.

Options

-c comment

Comment field.

-d dir

Home directory. The default is to use user as the directory name under the home directory specified with the -D option.

-e date

Account expiration date. date is in the format MM/DD/YYYY. Two-digit year fields are also accepted. The value is stored as the number of days since January 1, 1970. This option requires the use of shadow passwords.

-f days

Permanently disable account this many days after the password has expired. A value of -1 disables this feature. This option requires the use of shadow passwords.

-g group

Initial group name or ID number. If a different default group has not been specified using the -D option, the default group is 1.

-G groups

Supplementary groups given by name or number in a comma-separated list with no whitespace.

-k [dir]

Copy default files to the user’s home directory. Meaningful only when used with the -m option. Default files are copied from /etc/skel/ unless an alternate dir is specified.

-m

Make user’s home directory if it does not exist. The default is not to make the home directory.

-M

Do not create a home directory for the user, even if the system default in /etc/login.defs is to create one.

-n

Red ...

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Publisher Resources

ISBN: 0596004826