System administration command. Remove corrupt or duplicate entries in the /etc/passwd and /etc/shadow files. pwck will prompt for a “yes” or “no” before deleting entries. If the user replies “no,” the program will exit. Alternate passwd and shadow files can be checked. If correctable errors are found, the user will be encouraged to run the usermod command.
Run in noninteractive read-only mode, answering all questions no.
One or more bad password entries found.
Could not open password files.
Could not lock password files.
Could not write password files.