The dialog box appears with the prompt and the editable initial string at the entry point. Null text entries are accepted. The x,y,w, and h arguments are optional. GrADS will use the default settings if they are omitted entirely or set to -1. The cursor must be inside the dialog box to allow text entry or editing to occur.
All text is centered in the dialog box.
See the set dialog refrence page for details on controlling the color properties of the dialog box widget.