3.2 Text Prompt System

Commands require various arguments, including numbers, filenames, yes/no responses, character strings, and lists. A uniform interface to this input is provided by the text prompt system. A prompt consists of a prompt string, followed by an optional units string enclosed in parentheses, followed by a default value enclosed in square brackets. The following shows some examples of prompts:

 filled-mesh? [no] <Enter>


 shrink-factor [0.1] <Enter>


 line-weight [1] <Enter>


 title [""] <Enter>

The default value for a prompt is accepted by pressing <Enter> on the keyboard or typing a , (comma).

Note that a comma is not a separator. It is a separate token that indicates a default value. The sequence " 1,2'' results in three values; the number 1 for the first prompt, the default value for the second prompt, and the number 2 for the third prompt.

A short help message can be displayed at any prompt by entering a ?. (See Section  3.6.)

To abort a prompt sequence, simply press <Ctrl C>.