Miscellaneous Fields

The :is=: field may be used at the start of the application to specify any string sent to the terminal to set or reset certain options on the terminal. For example, the Wyse 60 can be set to display 24 or 25 lines. If the termcap entry indicates a 24 line display (with :li#24:) then the :is=: string can be used to force the terminal into a 24-line mode at the start of the application. (This is possible because there is an escape sequence on the Wyse 60 to set the number of lines.) The Wyse 60 manual says that "ESC e (" will set a 24 line display. This translates into termcap as :is=\Ee(:. This could annoy a user who prefers a 25-line display, in which case, a termcap entry could be created with a :li#25: field.

Another example involves different terminals that belong to the same family. Such terminals, while basically similar, may have minor differences in features. Instead of creating a different, complete termcap entry for each terminal, a "base entry" is created that applies to all terminals in the family. Then, for each terminal in the family, a unique entry is created that references the base entry but includes enhancements and changes. The following example shows how to create a 25-line display, if an entry for a Wyse 60 indicates a 24-line display:

wyse60|wy60|Wyse 60 terminal:\
 :li#24:co#80:am:cl=\E*:cm=\E=%+ %+ :\
 :bs:nd=^L:up=^K:do=\n:ho=\E{:\
 :cd=\EY:ce=\ET:\
 :al=\EE:dl=\ER:im=:ei=:ic=\EQ:dc=\EW:\
 :k0=^A@\r:k1=^AA\r:k2=^AB\r:k3=^AC\r:k4=^AD\r:\
 :k5=^AE\r:k6=^AF\r:k7=^AG\r:k8=^AH\r:k9=^AI\r:\
 :kl=^H:kr=^L:ku=^K:kd=\n:
wyse60-25:li#25:tc=wyse60:

A new entry was created called "wyse60-25". The :li#25: field specifies a 25-line display. The :tc=wyse60: field means that the rest of the entry is copied from the "wyse60" entry. Even though the "wyse60" entry already contains a :li#24: field, it is overridden by the :li#25: field in the "wyse60-25" entry. If a :tc=: field is used it must be the last field of an entry.