newgrp(1)

NAME

newgrp — switch to a new group

SYNOPSIS

newgrp [-] [group]

DESCRIPTION

The newgrp command changes your group ID without changing your user ID and replaces your current shell with a new one.

If you specify group, the change is successful if group exists and either your user ID is a member of the new group, or group has a password and you can supply it from the terminal.

If you omit group, newgroup changes to the group specified in your entry in the password file, /etc/passwd.

Whether the group is changed successfully or not, or the new group is the same as the old one or not, newgrp proceeds to replace your current shell with the one specified in the shell field of your password file entry. If that field is empty, newgrp uses the POSIX shell, /usr/bin/sh (see sh-posix(1)).

If you specify - (hyphen) as the first argument, the new shell starts up as if you had just logged in. If you omit -, the new shell starts up as if you had invoked it as a subshell.

You remain logged in and the current directory is unchanged, but calculations of access permissions to files are performed with respect to the new real and effective group IDs.

Exported variables retain their values and are passed to the new shell. All unexported variables are deleted, but the new shell may reset them to default values.

Since the current process is replaced when the new shell is started, exiting from the new shell has the same effect as exiting from the shell in which newgrp was executed.

EXTERNAL INFLUENCES

International Code Set Support

Characters from the 7-bit USASCII code set are supported in group names (see ascii(5)).

DIAGNOSTICS

The newgrp command issues the following error messages:

Sorry: Your user ID does not qualify as a group member.
Unknown group: The group name does not exist in /etc/group.
Permission denied: If a password is required, it must come from a terminal.
You have no shell: Standard input is not a terminal file, causing the new shell to fail.

EXAMPLES

To change from your current group to group users without executing the login routines:

newgrp users 

To change from your current group to group users and execute the login routines:

newgrp - users 

WARNINGS

There is no convenient way to enter a password into /etc/group.

The use of group passwords is not recommended because, by their very nature, they encourage poor security practices. Group passwords may be eliminated in future HP-UX releases.

If the specified group to newgrp has multiple inconsistent entries (i.e. the group id or/and password are different) in the group database, newgrp will consider the group id and password of the first matched group entry as the correct group id and password for the group.

FILES

/etc/group: System group file
/etc/passwd: System password file

STANDARDS CONFORMANCE

newgrp: SVID2, SVID3, XPG2, XPG3, XPG4