newgrp

Updated: April 19, 2023

Change to a new group

Syntax:

newgrp [-l|-s] [group]

Runs on:

QNX Neutrino

Options:

-l
(“el”) Change the environment to what would be expected if the user actually logged in again.
-s
Set the group ID of the parent; don't exec() a login shell.
group
A group name.

Description:

The newgrp utility starts a new shell with a new real and effective group ID. The user remains logged in and the current directory doesn't change, but file access permissions are based on the new real and effective group IDs.

Note: This utility needs to have the setuid (“set user ID”) bit set in its permissions. If you use mkefs, mketfs, mkifs, or mkqnx6fs on a Windows host to include this utility in an image, use the perms attribute to specify its permissions explicitly, and the uid and gid attributes to set the ownership correctly.

If no operands are specified, newgrp changes the group ID back to the group identified in the invoking user's entry in /etc/passwd.

If you don't use the -l option, the environment variables remain unchanged.

Note that the QNX Neutrino RTOS doesn't support group passwords. Only the user root may change the group ID to a group that it doesn't belong to.

Files:

/etc/group
Contains information on the group IDs in the system.
/etc/passwd
Contains information on the user IDs in the system.

See the passwd utility's “Files” section for a brief description of the format of these files.