VT220(1)                                                 VT220(1)


NAME
       vt220 - define SHIFTED function keys on VT220 terminal



SYNTAX
       vt220 [ -cil ] [ keyname keystring ] ...

DESCRIPTION
       Vt220  sets  up  a "vt220 terminal" in vt200 mode to allow
       user definition of the SHIFTED function keys. Each keyname
       specified on the command line will be loaded with the cor-
       responding keystring.  A keyname is one of the   following
       "words": F6 F7 F8 F9 F10 F11 ESC F12 BS F13 LF F14 HELP DO
       F17 F18 F19 F20.  Keystrings must  be  quoted  if  spaces,
       tabs, or shell metacharacters are included.

       Vt220  expects to receive some combination of option flags
       and/or argument pair(s), otherwise  an  usage  message  is
       printed.

       The options are:

       -c     Clears  all SHIFTED function key definitions before
              setting them to user defined strings.

       -i     Read the  initialization  file  $HOME/.vt220rc  for
              SHIFTED  function  key  definitions.   This is done
              before any argument pair specified on  the  command
              line is processed.  Each line in the file must con-
              sist of two fields (separated by  spaces  or  tabs)
              where the first field is the keyname and the second
              field is the keystring.  The second  field  extends
              to  the  end  of  the  line;  thus  a keystring may
              include spaces or tabs.  A newline (return) may  be
              specified within the string by using the C Language
              notation for newline (\n).

       -l     Locks the function keys  from  further  definition.
              Locking  occurs after processing the initialization
              file (if the "i" option is specified) and any argu-
              ment  pairs.   The only way to unlock is by turning
              the power off.

EXAMPLES
       vt220 -ci
       vt220 F6 'nroff -ms '
       vt220 -i F20 'cc -O -c '
       vt220 -l HELP man

OTHER FEATURES
       Pressing the function keys without using  the  shift  key,
       generates a string of characters.  With csh(1) this string
       can be aliased to some command.  For example:
            alias ^[[17~ "ls -CR | more"
       where ^[[17~ is what is generated by pressing the F6  key.



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VT220(1)                                                 VT220(1)


       Therefore  F6  can  perform  two  commands,  depending  if
       pressed with/without the SHIFT key.

       Vt220 can be called from your  .login  or  .profile  file.
       Typically  an  user  will create a initialization file and
       include a line like
            vt220 -ci
       OR
            vt220 -cil
       in the above mentioned files.  This way the SHIFTED  func-
       tion  keys will be set to your favorite commands when log-
       ging in.

CAVEATS
       If the SHIFTED function keys are unlocked, redefinition of
       a SHIFTED function key will rewrite the old string.

       There  are  256  bytes  available for the SHIFTED function
       keys.   Space  is  supplied  on  a  first-come/first-serve
       basis.  After the 256 bytes are used, you can't define any
       more keys unless space is cleared.  This can  be  done  by
       redefining a key to contain a string of fewer bytes.

       All  key  definitions  are stored in volatile RAM, and are
       lost when terminal power is lost.

       The ESC key (unshifted) no  longer  generates  the  proper
       escape  character.  This is of particular importance since
       many editors require use  of the ESC key.  Here  are  some
       available alternatives:

            The  escape  character  can be generated by typing ^[
            (control-[).

            Use vt220 as follows (note ^[ is control-[)
                 vt220 ESC '^['
            This will require you to press the SHIFT key and  ESC
            to generate the escape sequence.

            Some  editors, allow other character(s) to be substi-
            tuted for the  escape  character.  For  example  with
            emacs include this line in your .emacs_pro:
                (bind-to-key "ESC-prefix" "\033[23~")
            Thus  when  the  ESC key is pressed, emacs will allow
            the characters generated (^[[23~) to perform the same
            function as the escape character.

FILES
       $HOME/.vt220rc - initialization file

SEE ALSO
       VT220 Programmer Reference Manual
       VT220 Programmer Pocket Guide




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VT220(1)                                                 VT220(1)



























































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