HP(C)                                UNIX System V



     Name
          hp - handle special functions of Hewlett-Packard terminals


     Syntax
          hp [ -e ] [ -m ]


     Description
          hp supports special functions of  the  Hewlett-Packard  2640
          series  of  terminals, with the primary purpose of producing
          accurate representations of most nroff  output.   A  typical
          usage is in conjunction with text processing software:

               nroff -h files ... | hp

          Regardless of the hardware  options  on  your  terminal,  hp
          tries  to  do  sensible  things with underlining and reverse
          line-feeds.    If   the   terminal   has    the    ``display
          enhancements''  feature,  subscripts and superscripts can be
          indicated in distinct ways.  If it has  the  ``mathematical-
          symbol''  feature, Greek and other special characters can be
          displayed.

          The flags are as follows:

          -e   It is assumed that  your  terminal  has  the  ``display
               enhancements''  feature,  and so maximal use is made of
               the added display  modes.   Overstruck  characters  are
               presented  in  the  Underlined  mode.  Superscripts are
               shown in Half-bright  mode,  and  subscripts  in  Half-
               bright,  Underlined  mode.  If this flag is omitted, hp
               assumes  that  your  terminal   lacks   the   ``display
               enhancements''  feature.   In this case, all overstruck
               characters, subscripts, and superscripts are  displayed
               in Inverse Video mode, i.e., dark-on-light, rather than
               the usual light-on-dark.
          -m   Requests minimization of output by changing newlines to
               ^M's.   Any  contiguous sequence of 3 or more new-lines
               is converted into a sequence of only 2 new-lines; i.e.,
               any  number  of  successive blank lines produces only a
               single blank output line.  This allows  you  to  retain
               more actual text on the screen.

          With regard  to  Greek  and  other  special  characters,  hp
          provides  the  same  set  as  300(C), except that ``not'' is
          approximated by a right arrow, and only the top half of  the
          integral sign is shown.


     Diagnostics
          line too long if the representation of a line exceeds  1,024
          characters.
          The exit codes are 0  for  normal  termination,  2  for  all
          errors.


     See Also
          300(C), greek(C)


     Notes
          An  ``overstriking  sequence''  is  defined  as  a  printing
          character  followed  by  a  backspace  followed  by  another
          printing character.  In such sequences, if  either  printing
          character  is an underscore, the other printing character is
          shown underlined or in Inverse Video;  otherwise,  only  the
          first  printing  character is shown (again, underlined or in
          Inverse Video).  Nothing special is done if a  backspace  is
          adjacent  to  an  ASCII  control  character.   Sequences  of
          control characters (e.g.,  reverse  line-feeds,  backspaces)
          can   make   text   ``disappear''.   In  particular,  tables
          generated by tbl(CT) that contain vertical lines will  often
          be  missing the lines of text that contain the ``foot'' of a
          vertical line, unless the  input  to  hp  is  piped  through
          col(C).

          Although some terminals  do  provide  numerical  superscript
          characters, no attempt is made to display them.


     (printed 2/15/90)                                      HP(C)