.TH PROOF 1
.SH NAME
proof \- troff output interpreter
.SH SYNOPSIS
.B proof
[
.BI -m mag
]
[
.BI -/ nview
]
[
.B -F
.I dir
]
[
.B -d
]
[
.I file
]
.SH DESCRIPTION
.I Proof
reads
.IR troff (1)
intermediate language from
.I file
or standard input
and simulates the resulting pages on the screen.
.PP
After a page of text is displayed,
.I proof
pauses for a command from the keyboard.
The typed commands are:
.TP \w'newline\ \ \ 'u
newline
Go on to next page of text.
.TP
.B -
Go back to the previous page.
.TP
.B q
Quit.
.TP
.BI p n
Print page
.I 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.
.TP
.I n
Same as
.BI p n .
.TP
.B c
Clear the screen, then wait for another command.
.TP
.BI m mag
Change the magnification at which the output is printed.
Normally it is printed with magnification .9;
.IR mag "=.5"
shrinks it to half size;
.IR mag "=2"
doubles the size.
.TP
.BI x val
Move everything
.I val
screen pixels to the right (left, if
.I val
is negative).
.TP
.BI y val
Move everything
.I val
screen pixels down (up, if
.I val
is negative).
.TP
.BI / nview
Split the window into
.I nview
pieces.  The current page goes into the rightmost, bottommost piece,
and previous pages are shown in the other pieces.
.TP
.BI "-F " dir
Use
.I dir
for fonts instead of
.BR /lib/font/bit .
.TP
.B d
Toggle the debug flag.
.PD
.PP
The
.BR m ,
.BR / ,
and
.B d
commands are also available as command line options.
.SH FILES
.TF /lib/font/bit/MAP
.TP
.B /lib/font/bit/*
fonts
.TP
.B /lib/font/bit/MAP
how to convert troff output fonts and character names
into screen fonts and character numbers
.SH SEE ALSO
.IR lp (1), 
.IR psi (1)
.br
Brian W. Kernighan,
.I A Typesetter-independent Troff
