+</PRE><H3><a name="h3-Field-validation">Field validation</a></H3><PRE>
+ The form library makes updates to the window associated
+ with form fields rather than directly to the field buf-
+ fers.
+
+ The form driver provides low-level control over updates to
+ the form fields. The form driver also provides for vali-
+ dating modified fields to ensure that the contents meet
+ whatever constraints an application may attach using
+ <STRONG>set_field_type</STRONG>.
+
+ You can validate a field without making any changes to it
+ using <STRONG>REQ_VALIDATION</STRONG>. The form driver also validates a
+ field in these cases:
+
+ <STRONG>o</STRONG> a call to <STRONG>set_current_field</STRONG> attempts to move to a dif-
+ ferent field.
+
+ <STRONG>o</STRONG> a call to <STRONG>set_current_page</STRONG> attempts to move to a dif-
+ ferent page of the form.
+
+ <STRONG>o</STRONG> a request attempts to move to a different field.
+
+ <STRONG>o</STRONG> a request attempts to move to a different page of the
+ form.
+
+ In each case, the move fails if the field is invalid.
+
+ If the modified field is valid, the form driver copies the
+ modified data from the window associated with the field to
+ the field buffer.
+
+
+</PRE><H3><a name="h3-Mouse-handling">Mouse handling</a></H3><PRE>