NAME

newgrp − log in to a new group

SYNOPSIS

newgrp [−] [ group ]

DESCRIPTION

The newgrp command changes a user’s group identification.  The user remains 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.  The user is always given a new shell, replacing the current shell, by newgrp, regardless of whether it terminated successfully or due to an error condition (i.e., unknown group).

Exported variables retain their values after invoking newgrp; however, all unexported variables are either reset to their default value or set to null. System variables (such as PS1, PS2, PATH, MAIL, and HOME), unless exported by the system or explicitly exported by the user, are reset to default values. For example, a user has a primary prompt string (PS1) other than $ (default) and has not exported PS1.  After an invocation of newgrp , successful or not, their PS1 will now be set to the default prompt string $.  Note that the shell command export [see sh(1)] is the method to export variables so that they retain their assigned value when invoking new shells. 

With no arguments, newgrp changes the group identification back to the group specified in the user’s password file entry.  This is a way to exit the effect of an earlier newgrp command. 

If the first argument to newgrp is a −, the environment is changed to what would be expected if the user actually logged in again as a member of the new group. 

A password is demanded if the group has a password and the user does not, or if the group has a password and the user is not listed in /etc/group as being a member of that group. 

FILES

/etc/groupsystem’s group file
/etc/passwdsystem’s password file

SEE ALSO

login(1), sh(1). 
group(4), passwd(4), environ(5) in the INTERACTIVE SDS Guide and Programmer’s Reference Manual.

BUGS

There is no convenient way to enter a password into /etc/group.  Use of group passwords is not encouraged, because, by their very nature, they encourage poor security practices.  Group passwords may disappear in the future. 

\*U  —  Version 1.0