more.1

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.\"	@(#)more.1	6.6 (Berkeley) 4/18/91
.\"
.TH MORE 1 "April 18, 1991"
.UC 4
.SH NAME
more, page \- file perusal filter for crt viewing
.SH SYNOPSIS
.B more
[
.B \-cdflsu
]
[
.B \-\fIn\fP
]
[
.B +\fIlinenumber\fP 
]
[
.B +/\fIpattern\fP
] [ name ...  ]
.LP
.B page
.I "more options"
.SH DESCRIPTION
.I  More
is a filter which allows examination of a continuous text
one screenful at a time on a soft-copy terminal.
It normally pauses after each screenful, printing --More--
at the bottom of the screen.
If the user then types a carriage return, one more line is displayed.
If the user hits a space,
another screenful is displayed.  Other possibilities are enumerated later.
.PP
The command line options are:
.TP
.I \-n
An integer which is the size (in lines) of the window which
.I more
will use instead of the default.
.TP
.B \-c
.I More
will draw each page by beginning at the top of the screen and erasing 
each line just before it draws on it.
This avoids scrolling the screen, making it easier to read while 
.I more 
is writing.
This option will be ignored if the terminal does not have the ability
to clear to the end of a line.
.TP
.B \-d
.I More
will prompt the user with the message "Press
space to continue, \'q\' to quit." at the end of each screenful,
and will respond to subsequent illegal user input by
printing "Press \'h\' for instructions." instead of ringing the bell.
This is useful if
.I more
is being used as a filter in some setting,
such as a class,
where many users may be unsophisticated.
.TP
.B \-f
This causes
.I more
to count logical, rather than screen lines.
That is, long lines are not folded.
This option is recommended if
.I nroff
output is being piped through
.I ul,
since the latter may generate escape sequences.
These escape sequences contain characters which would ordinarily occupy
screen positions, but which do not print when they are sent to the
terminal as part of an escape sequence.
Thus
.I more
may think that lines are longer than they actually are, and fold
lines erroneously.
.TP
.B \-l
Do
not treat ^\&L (form feed) specially.
If this option is not given,
.I more
will pause after any line that contains a ^\&L, as if the end of a
screenful had been reached.
Also, if a file begins with a form feed, the screen will be cleared
before the file is printed.
.TP
.B \-s
Squeeze multiple blank lines from the output, producing only one blank
line.  Especially helpful when viewing
.I nroff
output, this option maximizes the useful information present on the screen.
.TP
.B \-u
Normally,
.I more
will handle underlining such as produced by
.I nroff
in a manner appropriate to the particular terminal:  if the terminal can
perform underlining or has a stand-out mode,
.I more
will output appropriate escape sequences to enable underlining or stand-out
mode for underlined information in the source file.  The
.I \-u
option suppresses this processing.
.TP
.B +\fIlinenumber\fP
Start up at \fIlinenumber\fP.
.TP
.B +/\fIpattern\fP
Start up two lines before the line containing the
regular expression \fIpattern\fP.
.PP
If the program is invoked as
.I page,
then the screen is cleared before each screenful is printed (but only
if a full screenful is being printed), and
.I k
\- 1 rather
than
.I k
\- 2 lines are printed in each screenful, where
.I k
is the number of lines the terminal can display.
.PP
.I More
looks in the file
.I /etc/termcap
to determine terminal characteristics,
and to determine the default window size.
On a terminal capable of displaying 24 lines,
the default window size is 22 lines.
.PP
.I More
looks in the environment variable
.I MORE
to pre-set any flags desired.  For example, if you prefer to view files using
the
.I \-c
mode of operation, the
.I csh
command
.I "setenv MORE -c"
or the
.I sh
command sequence
.I "MORE='-c' ; export MORE"
would cause all invocations of
.I more ,
including invocations by programs such as
.I man
and
.I msgs ,
to use this mode.
Normally, the user will place the command sequence which sets up the
.I MORE
environment variable in the
.I .cshrc
or
.I .profile
file.
.PP
If
.I more
is reading from a file, rather than a pipe, then a percentage is displayed
along with the --More-- prompt.
This gives the fraction of the file (in characters, not lines) that has been
read so far.
.PP
Other sequences which may be typed when
.I more
pauses, and their effects, are as follows (\fIi\fP is an optional integer
argument, defaulting to 1) :
.PP
.IP \fIi\|\fP<space>
display
.I i
more lines, (or another screenful if no argument is given)
.PP
.IP ^D
display 11 more lines (a ``scroll'').
If
.I i
is given, then the scroll size is set to \fIi\|\fP.
.PP
.IP d
same as ^D (control-D)
.PP
.IP \fIi\|\fPz
same as typing a space except that \fIi\|\fP, if present, becomes the new
window size.
.PP
.IP \fIi\|\fPs
skip \fIi\|\fP lines and print a screenful of lines
.PP
.IP \fIi\|\fPf
skip \fIi\fP screenfuls and print a screenful of lines
.PP
.IP \fIi\|\fPb
skip back \fIi\fP screenfuls and print a screenful of lines
.PP
.IP \fIi\|\fP^B
same as b
.PP
.IP "q or Q"
Exit from
.I more.
.PP 
.IP =
Display the current line number.
.PP
.IP v
Start up the editor
.I vi
at the current line.
.PP
.IP h
Help command; give a description of all the
.I more
commands.
.PP
.IP \fIi\|\fP/expr
search for the \fIi\|\fP-th occurrence of the regular expression \fIexpr.\fP
If there are less than \fIi\fP occurrences of \fIexpr\|\fP,
and the input is a file (rather than a pipe),
then the position in the file remains unchanged.
Otherwise, a screenful is displayed, starting two lines before the place
where the expression was found.
The user's erase and kill characters may be used to edit the regular
expression.
Erasing back past the first column cancels the search command.
.PP
.IP \fIi\|\fPn
search for the \fIi\|\fP-th occurrence of the last regular expression entered.
.PP
.IP \'
(single quote) Go to the point from which the last search started.
If no search has been performed in the current file, this command
goes back to the beginning of the file.
.PP
.IP !command
invoke a shell with \fIcommand\|\fP. 
The characters `%' and `!' in "command" are replaced with the
current file name and the previous shell command respectively.
If there is no current file name, `%' is not expanded.
The sequences "\\%" and "\\!" are replaced by "%" and "!" respectively.
.PP
.IP \fIi\|\fP:n
skip to the \fIi\|\fP-th next file given in the command line
(skips to last file if n doesn't make sense)
.PP
.IP \fIi\|\fP:p
skip to the \fIi\|\fP-th previous file given in the command line.
If this command is given in the middle of printing out a
file, then
.I more
goes back to the beginning of the file. If \fIi\fP doesn't make sense,
.I more
skips back to the first file.
If
.I more
is not reading from a file, the bell is rung and nothing else happens.
.PP
.IP :f
display the current file name and line number.
.PP
.IP ":q or :Q"
exit from 
.I more
(same as q or Q).
.PP
.IP .
(dot) repeat the previous command.
.PP
The commands take effect immediately, i.e., it is not necessary to
type a carriage return.
Up to the time when the command character itself is given,
the user may hit the line kill character to cancel the numerical
argument being formed.
In addition, the user may hit the erase character to redisplay the
--More--(xx%) message.
.PP
At any time when output is being sent to the terminal, the user can
hit the quit key (normally control\-\\).
.I More
will stop sending output, and will display the usual --More--
prompt.
The user may then enter one of the above commands in the normal manner.
Unfortunately, some output is lost when this is done, due to the
fact that any characters waiting in the terminal's output queue
are flushed when the quit signal occurs.
.PP
The terminal is set to
.I noecho
mode by this program so that the output can be continuous.
What you type will thus not show on your terminal, except for the / and !
commands.
.PP
If the standard output is not a teletype, then
.I more
acts just like
.I cat,
except that a header is printed before each file (if there is
more than one).
.PP
.DT
A sample usage of
.I more
in previewing
.I nroff
output would be
.PP
	nroff \-ms +2 doc.n | more -s
.SH FILES
.DT
/etc/termcap		Terminal data base
.br
/usr/lib/more.help	Help file
.SH "SEE ALSO"
csh(1), man(1), msgs(1), script(1), sh(1), environ(7)
.SH BUGS
Skipping backwards is too slow on large files.