ID - User Identity Display

Print user and group identity information including UID (user ID), GID (group ID), and all supplementary group memberships. Essential for permission debugging and understanding process security context.

Usage

id-tool [options] [username]

Without arguments, shows information for the current user. Specify a username to query another user's identity details.

Options

• -u: Show only effective user ID
• -g: Show only effective group ID
• -G: Show all supplementary group IDs
• -n: Display names instead of numeric IDs

Examples

# Show full identity
id-tool

# Show user ID only
id-tool -u

# Show all groups for user
id-tool -G www-data