chgpasswd

chgpasswd [OPTIONS]
(Input is typically provided via standard input, e.g., echo 'groupname:new_password' | chgpasswd)

-R, --root CHROOT_DIR
    Specifies a different chroot directory to apply password changes within.

STDIN Input
    The command expects input in the format 'groupname:new_password' on standard input for each group.

The chgpasswd command, while not a standard or widely available utility on most modern Linux distributions, would conceptually serve to update group passwords, typically in a batch or non-interactive manner.

If present, its primary purpose would be to allow system administrators to programmatically change passwords for multiple groups at once, reading group-password pairs from standard input or a specified file. This contrasts with interactive utilities like gpasswd, which is the standard command for managing group passwords and memberships, including changing a single group's password.

In environments where chgpasswd might exist (e.g., highly specialized systems or older distributions), it would be invaluable for scripting tasks, such as initial system setup, migrations, or automated password rotation policies for group accounts. Its functionality would likely mirror that of chpasswd (for user passwords), but adapted for group contexts.

Non-Standard Command:
The most significant caveat is that chgpasswd is not a standard Linux command and is rarely found on modern distributions. The correct and widely available utility for managing group passwords is gpasswd.

Security Implications:
If such a command were used, feeding plain-text passwords through standard input or files poses security risks. Care must be taken to secure input data.

Privileges:
Changing group passwords typically requires root privileges.

For managing group passwords and membership, gpasswd is the universally accepted and comprehensive utility. It supports changing group passwords interactively, adding/removing members, and setting administrative passwords for group management. chgpasswd would only focus on batch password changes, making it less versatile.

In scenarios where chgpasswd might be implemented, its primary use would be in scripts. For example, to set initial passwords for many groups during system deployment, or to comply with security policies requiring regular, automated password resets for service-related groups.

While not a commonly adopted standalone utility, the concept behind chgpasswd mirrors the need for batch operations in system administration. Its hypothetical existence would likely stem from a desire to extend the functionality of chpasswd (for users) to group management. Historically, the gpasswd command has evolved to handle both interactive and programmatic group password changes, effectively absorbing the functionality that a separate chgpasswd might offer, thus making a dedicated command largely redundant in mainstream Linux distributions.

gpasswd(1), passwd(1), chpasswd(8), group(5), shadow(5)