```

     PROOF(1)                                                 PROOF(1)

     NAME
          proof - troff output interpreter

     SYNOPSIS
          proof [ -mmag ] [ -/nview ] [ -F dir ] [ -d ] [ file ]

     DESCRIPTION
          Proof reads troff(1) intermediate language from file or
          standard input and simulates the resulting pages on the
          screen.

          After a page of text is displayed, proof pauses for a com-
          mand from the keyboard.  The typed commands are:

          newline   Go on to next page of text.

          -         Go back to the previous page.

          q         Quit.

          pn        Print page n. An out-of-bounds page number means
                    the end nearer to that number; a missing number
                    means the current page; a signed number means an
                    offset to the current page.

          n         Same as pn.

          c         Clear the screen, then wait for another command.

          mmag      Change the magnification at which the output is
                    printed.  Normally it is printed with magnifica-
                    tion .9; mag=.5 shrinks it to half size; mag=2
                    doubles the size.

          xval      Move everything val screen pixels to the right
                    (left, if val is negative).

          yval      Move everything val screen pixels down (up, if val
                    is negative).

          /nview    Split the window into nview pieces.  The current
                    page goes into the rightmost, bottommost piece,
                    and previous pages are shown in the other pieces.

          -F dir    Use dir for fonts instead of /lib/font/bit.

          d         Toggle the debug flag.

          These commands are also available, under slightly different
          form, from a menu on button 3.  The pan menu item allows
          arbitrary positioning of the page: after selecting pan,
          press the mouse button again and hold it down while moving
          the page to the desired location.  The page will be
          redisplayed in its entirety when the button is released.
          Mouse button 1 also pans, without the need for selecting
          from a menu.

          The m, x, y, F, /, and d commands are also available as com-
          mand line options.

     FILES
          /lib/font/bit/*    fonts
          /lib/font/bit/MAP  how to convert troff output fonts and
                             character names into screen fonts and
                             character numbers

     SOURCE
          /sys/src/cmd/proof

     SEE ALSO
          lp(1), gs(1), page(1)
          J. F. Ossanna and B. W. Kernighan, ``Troff User's Manual'',
          /sys/doc/troff.pdf

```