bcrontab: Manage users crontab files

SYNOPSIS

bcrontab [ -u user ] file

bcrontab [ -u user ] { -l | -r | -e }

bcrontab interfaces with the bcron-spool daemon to manage crontab files in the privileged spool directory.

-u user: Tell bcron-spool that we are acting on behalf of the named user. bcron-spool will only accept the username if bcrontab is running as either root or the same user ID as the named user.
-l: List the cronab crontab to standard output.
-r: Remove the user's crontab.
-e: Edit the current crontab.

VISUAL: If this is set, it is used as the editor to invoke to edit a crontab.
EDITOR: If $VISUAL is not set and this is, it is used as the editor to invoke to edit a crontab. If neither are set, /bin/vi is used.
BCRON_SOCKET: The path to the named socket used to communicate with bcron-spool. Defaults to /var/run/bcron-spool.
LOGNAME
USER: These two variables are used, in order, to determine the user name invoking the program. One must be set if the -u option is not used.

bcrontab tries to writes a temporary file into the current directory, and then into /tmp if that fails, in order to edit the current crontab.