group - Group file
The /etc/group database contains the following information
for each group: Group name Encrypted password Numerical
group ID A comma-separated list of all users allowed in
Do not put any spaces between a comma and a username;
otherwise, the username following the comma
will not be made a part of the desired group.
The /etc/group file is an ASCII file, with the fields separated
by colons. Each group is separated from the next by
a new line. If the password field is null, no password is
Because of the encrypted passwords, it can and does have
general read permission and can be used, for example, to
map numerical group IDs to names.
Note that commands or scripts used for adding users to
groups are subject to the 225 character limit on line
lengths. However, you can split lines as appropriate.
Increasing the number of groups that a user is in beyond
16 can affect services that use ONC RPC. Tru64 UNIX ONC
RPC supports up to 32 groups for compatibility with ULTRIX
Version 4.2 and higher. Other vendors may support only 16
groups. ULTRIX versions before 4.2 support up to 8
groups. Users who increase their group membership beyond
8 or 16 groups will not be able to NFS mount file systems
from servers that only support 8 or 16 groups over NFS. In
addition, if root group membership is increased beyond 8
or 16, the NIS service will not work in a mixed NIS server
environment where the servers support only 8 or 16 groups.
The addgroup command limits the length of a group name to
eight characters or less.
Commands: addgroup(8), groupadd(8), adduser(8),
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