listing for N
newgrp - Changes primary group identification of a shell process
newgrp [-l] [group]
newgrp [-] [group]
The C shell has a built-in version of the newgrp command. If you are
using the C shell, and want to guarantee that you are using the
command described here, you must specify the full path
/usr/bin/newgrp. See the csh(1) reference page for a description of
the built-in command.
Interfaces documented on this reference page conform to industry standards
Refer to the standards(5) reference page for more information about
industry standards and associated tags.
-l Changes the login environment to what would be expected if the user
logged in again.
- Changes the login environment to what would be expected if the user
logged in again. (Obsolescent)
A group name from the group database or a non-negative numeric group
ID. Specifies the group ID to which the real and effective group IDs
will be set. If group is a non-negative numeric string and exists in
the group database as a group name, the numeric group ID associated
with that group name will be used as the group ID.
The newgrp command changes the primary group identification of the current
shell process to group. You remain logged in and the current directory is
unchanged, but calculations of access permissions to files are performed
with respect to the primary group ID.
If you do not specify group, newgrp changes the group identification back
to that specified for the current user in the /etc/passwd file. Only
exported environment variables retain their values after you invoke newgrp.
Otherwise, variables with a default value are reset to that default.
If a password is required for the specified group, and you are not listed
as a member of that group in the group database, you are prompted to enter
the correct password for that group. If you are listed as a member of that
group, no password is requested. If no password is required for the
specified group, only users listed as members of that group can change to
[Tru64 UNIX] Only a user with superuser authority can change the primary
group of the shell process to one to which that user does not belong.
[Tru64 UNIX] When you invoke the newgrp command from a shell, the shell
executes the command without forking a new process. Therefore, the shell
you were using when you issued the newgrp command is unavailable after the
newgrp command finishes.
1. [Tru64 UNIX] The newgrp command is also a built-in command for csh.
2. There is no convenient way to enter a password into the group
database. Use of group passwords is not encouraged because by their
very nature they encourage poor security practices.
If newgrp succeeds in creating a new shell execution environment, whether
or not the group identification was changed successfully, the exit status
will be the exit status of the shell. Otherwise, a non-zero exit value is
The exit status of newgrp is generally inapplicable.
The following environment variables affect the execution of newgrp:
Provides a default value for the internationalization variables that
are unset or null. If LANG is unset or null, the corresponding value
from the default locale is used. If any of the internationalization
variables contain an invalid setting, the utility behaves as if none of
the variables had been defined.
If set to a non-empty string value, overrides the values of all the
other internationalization variables.
Determines the locale for the interpretation of sequences of bytes of
text data as characters (for example, single-byte as opposed to
multibyte characters in arguments).
Determines the locale for the format and contents of diagnostic
messages written to standard error.
Determines the location of message catalogues for the processing of
Group names declared on the system
Commands: csh(1), groups(1), id(1), login(1), Bourne shell sh(1b), POSIX
Files: group(4), passwd(4)
listing for N