[CTX] [ALL]
CHARCODE parameter* ==  CHARCODE=[inputCode/]outputCode[:[tosv][:connMap]]
        outputCode  ==  charCode
          charCode  ==  iso-2022-jp | euc-jp | shift_jis | utf-8 | us-ascii |
                               JIS | EUC | SJIS | UTF8 | ASCII | guess
           connMap  ==  [ProtoList][:[dstHostList][:[srcHostList]]]
                    --  restriction: applicable to HTTP, FTP, SMTP, POP,
                                     NNTP, Telnet, Tcprelay
                    --  default: none