Enter/return on the 'Submit' button, I suppose. The rationale may have been "Start at the beginning of the form, keep hitting Enter after filling in each field, and it will submit itself when you're done."
Some terminal software would use a function key that would be labelled "Execute". You'd usually have a template to put over the function keys to tell you what does what.
Some terminal software would use a function key that would be labelled "Execute". You'd usually have a template to put over the function keys to tell you what does what.