The ckdate utility prompts a user and validates the response. It defines, among other things, a prompt message whose response should be a date, text for help and error messages,
and a default value (which will be returned if the user responds with a RETURN). The user response must match the defined format for a date.
All messages are limited in length to 70 characters and are formatted automatically. Any white space used in the definition (including newline) is stripped. The -W option cancels the
automatic formatting. When a tilde is placed at the beginning or end of a message definition, the default text will be inserted at that point, allowing both custom text and the default text to be displayed.
If the prompt, help or error message is not defined, the default message (as defined under NOTES) will be displayed.
Three visual tool modules are linked to the ckdate command. They are errdate (which formats and displays an error message), helpdate (which
formats and displays a help message), and valdate (which validates a response). These modules should be used in conjunction with FML objects. In this instance, the FML object defines
the prompt. When format is defined in the errdate and helpdate modules, the messages will describe the expected format.