The grpck command removes corrupt or duplicate entries in the /etc/group and /etc/gshadow files. It generates warnings for other errors found. grpck will prompt for a “yes” or “no” before deleting entries. If the user replies “no,” the program will exit. If run in a read-only mode, the reply to all prompts is “no.” Alternate group and gshadow files can be checked. If other errors are found, the user will be encouraged to run the groupmod command.
Syntax:
# grpck [option] [files]
Command Options
There are only 2 command options which you can use with this command.
| Command option | Description |
|---|---|
| -r | Read only mode |
| -s | Sort group id |
Exit Codes
- 0: Success.
- 1: Syntax error.
- 2: One or more bad group entries found.
- 3: Could not open group files.
- 4: Could not lock group files.
- 5: Could not write group files.
Examples of grpck Command
1. Verify the group account file:
# grpck /etc/group
2. Verify the shadow file:
# grpck /etc/gshadow