form_driver - command-processing loop of the form system
int form_driver(FORM *form, int c);
Once a form has been posted (displayed), you should funnel input events to it through form_driver. This routine has two major input cases;
either the input is a form navigation request or it's a printable ASCII character. The form driver requests are as follows:
Move to the next page.
Move to the previous page.
Move to the first page.
Move to the last field.
Move to the next field.
Move to the previous field.
Move to the first field.
Move to the last field.
Move to the sorted next field.
Move to the sorted previous field.
Move to the sorted first field.
Move to the sorted last field.
Move left to a field.
Move right to a field.
Move up to a field.
Move down to a field.
Move to the next char.
Move to the previous char.
Move to the next line.
Move to the previous line.
Move to the next word.
Move to the previous word.
Move to the beginning of the field.
Move to the end of the field.
Move to the beginning of the line.
Move to the end of the line.
Move left in the field.
Move right in the field.
Move up in the field.
Move down in the field.
Insert or overlay a new line.
Insert a blank at the cursor.
Insert a blank line at the cursor.
Delete character at the cursor.
Delete character before the cursor.
Delete line at the cursor.
Delete blank-delimited word at the cursor.
Clear to end of line from cursor.
Clear to end of field from cursor.
Clear the entire field.
Enter overlay mode.
Enter insert mode.
Scroll the field forward a line.
Scroll the field backward a line.
Scroll the field forward a page.
Scroll the field backward a page.
Scroll the field forward half a page.
Scroll the field backward half a page.
Scroll the field forward a character.
Scroll the field backward a character.
Horizontal scroll the field forward a line.
Horizontal scroll the field backward a line.
Horizontal scroll the field forward half a line.
Horizontal scroll the field backward half a line.
Display next field choice.
Display previous field choice.
If the second argument is a printable ASCII character, the driver places it in the current position in the current field. If it is one of
the forms requests listed above, that request is executed.
If the second argument is neither printable ASCII nor one of the above pre-defined form requests, the driver assumes it is an application-
specific command and returns E_UNKNOWN_COMMAND. Application-defined commands should be defined relative to MAX_COMMAND, the maximum value
of these pre-defined requests.
form_driver return one of the following error codes:
E_OK The routine succeeded.
System error occurred (see errno).
Routine detected an incorrect or out-of-range argument.
Routine was called from an initialization or termination function.
The form has not been posted.
The form driver code saw an unknown request code.
Contents of field is invalid.
The form driver could not process the request.
The header file <form.h> automatically includes the header files <curses.h>.
These routines emulate the System V forms library. They were not supported on Version 7 or BSD versions.
Juergen Pfeifer. Manual pages and adaptation for new curses by Eric S. Raymond.