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PROLOG | NAME | SYNOPSIS | DESCRIPTION | OPTIONS | OPERANDS | STDIN | INPUT FILES | ENVIRONMENT VARIABLES | ASYNCHRONOUS EVENTS | STDOUT | STDERR | OUTPUT FILES | EXTENDED DESCRIPTION | EXIT STATUS | CONSEQUENCES OF ERRORS | APPLICATION USAGE | EXAMPLES | RATIONALE | FUTURE DIRECTIONS | SEE ALSO | COPYRIGHT |
MORE(1P) POSIX Programmer's Manual MORE(1P)
This manual page is part of the POSIX Programmer's Manual. The Linux
implementation of this interface may differ (consult the
corresponding Linux manual page for details of Linux behavior), or
the interface may not be implemented on Linux.
more — display files on a page-by-page basis
more [−ceisu] [−n number] [−p command] [−t tagstring] [file...]
The more utility shall read files and either write them to the
terminal on a page-by-page basis or filter them to standard output.
If standard output is not a terminal device, all input files shall be
copied to standard output in their entirety, without modification,
except as specified for the −s option. If standard output is a
terminal device, the files shall be written a number of lines (one
screenful) at a time under the control of user commands. See the
EXTENDED DESCRIPTION section.
Certain block-mode terminals do not have all the capabilities
necessary to support the complete more definition; they are incapable
of accepting commands that are not terminated with a <newline>.
Implementations that support such terminals shall provide an
operating mode to more in which all commands can be terminated with a
<newline> on those terminals. This mode:
* Shall be documented in the system documentation
* Shall, at invocation, inform the user of the terminal deficiency
that requires the <newline> usage and provide instructions on how
this warning can be suppressed in future invocations
* Shall not be required for implementations supporting only fully
capable terminals
* Shall not affect commands already requiring <newline> characters
* Shall not affect users on the capable terminals from using more
as described in this volume of POSIX.1‐2008
The more utility shall conform to the Base Definitions volume of
POSIX.1‐2008, Section 12.2, Utility Syntax Guidelines, except that
'+' may be recognized as an option delimiter as well as '−'.
The following options shall be supported:
−c If a screen is to be written that has no lines in common
with the current screen, or more is writing its first
screen, more shall not scroll the screen, but instead shall
redraw each line of the screen in turn, from the top of the
screen to the bottom. In addition, if more is writing its
first screen, the screen shall be cleared. This option may
be silently ignored on devices with insufficient terminal
capabilities.
−e Exit immediately after writing the last line of the last
file in the argument list; see the EXTENDED DESCRIPTION
section.
−i Perform pattern matching in searches without regard to
case; see the Base Definitions volume of POSIX.1‐2008,
Section 9.2, Regular Expression General Requirements.
−n number Specify the number of lines per screenful. The number
argument is a positive decimal integer. The −n option shall
override any values obtained from any other source.
−p command
Each time a screen from a new file is displayed or
redisplayed (including as a result of more commands; for
example, :p), execute the more command(s) in the command
arguments in the order specified, as if entered by the user
after the first screen has been displayed. No intermediate
results shall be displayed (that is, if the command is a
movement to a screen different from the normal first
screen, only the screen resulting from the command shall be
displayed.) If any of the commands fail for any reason, an
informational message to this effect shall be written, and
no further commands specified using the −p option shall be
executed for this file.
−s Behave as if consecutive empty lines were a single empty
line.
−t tagstring
Write the screenful of the file containing the tag named by
the tagstring argument. See the ctags(1p) utility. The tags
feature represented by −t tagstring and the :t command is
optional. It shall be provided on any system that also
provides a conforming implementation of ctags; otherwise,
the use of −t produces undefined results.
The filename resulting from the −t option shall be
logically added as a prefix to the list of command line
files, as if specified by the user. If the tag named by the
tagstring argument is not found, it shall be an error, and
more shall take no further action.
If the tag specifies a line number, the first line of the
display shall contain the beginning of that line. If the
tag specifies a pattern, the first line of the display
shall contain the beginning of the matching text from the
first line of the file that contains that pattern. If the
line does not exist in the file or matching text is not
found, an informational message to this effect shall be
displayed, and more shall display the default screen as if
−t had not been specified.
If both the −t tagstring and −p command options are given,
the −t tagstring shall be processed first; that is, the
file and starting line for the display shall be as
specified by −t, and then the −p more command shall be
executed. If the line (matching text) specified by the −t
command does not exist (is not found), no −p more command
shall be executed for this file at any time.
−u Treat a <backspace> as a printable control character,
displayed as an implementation-defined character sequence
(see the EXTENDED DESCRIPTION section), suppressing
backspacing and the special handling that produces
underlined or standout mode text on some terminal types.
Also, do not ignore a <carriage-return> at the end of a
line.
The following operand shall be supported:
file A pathname of an input file. If no file operands are
specified, the standard input shall be used. If a file is
'−', the standard input shall be read at that point in the
sequence.
The standard input shall be used only if no file operands are
specified, or if a file operand is '−'.
The input files being examined shall be text files. If standard
output is a terminal, standard error shall be used to read commands
from the user. If standard output is a terminal, standard error is
not readable, and command input is needed, more may attempt to obtain
user commands from the controlling terminal (for example, /dev/tty);
otherwise, more shall terminate with an error indicating that it was
unable to read user commands. If standard output is not a terminal,
no error shall result if standard error cannot be opened for reading.
The following environment variables shall affect the execution of
more:
COLUMNS Override the system-selected horizontal display line size.
See the Base Definitions volume of POSIX.1‐2008, Chapter 8,
Environment Variables for valid values and results when it
is unset or null.
EDITOR Used by the v command to select an editor. See the EXTENDED
DESCRIPTION section.
LANG Provide a default value for the internationalization
variables that are unset or null. (See the Base Definitions
volume of POSIX.1‐2008, Section 8.2, Internationalization
Variables for the precedence of internationalization
variables used to determine the values of locale
categories.)
LC_ALL If set to a non-empty string value, override the values of
all the other internationalization variables.
LC_COLLATE
Determine the locale for the behavior of ranges,
equivalence classes, and multi-character collating elements
within regular expressions.
LC_CTYPE Determine the locale for the interpretation of sequences of
bytes of text data as characters (for example, single-byte
as opposed to multi-byte characters in arguments and input
files) and the behavior of character classes within regular
expressions.
LC_MESSAGES
Determine the locale that should be used to affect the
format and contents of diagnostic messages written to
standard error and informative messages written to standard
output.
NLSPATH Determine the location of message catalogs for the
processing of LC_MESSAGES.
LINES Override the system-selected vertical screen size, used as
the number of lines in a screenful. See the Base
Definitions volume of POSIX.1‐2008, Chapter 8, Environment
Variables for valid values and results when it is unset or
null. The −n option shall take precedence over the LINES
variable for determining the number of lines in a
screenful.
MORE Determine a string containing options described in the
OPTIONS section preceded with <hyphen> characters and
<blank>-separated as on the command line. Any command line
options shall be processed after those in the MORE
variable, as if the command line were:
more $MORE options operands
The MORE variable shall take precedence over the TERM and
LINES variables for determining the number of lines in a
screenful.
TERM Determine the name of the terminal type. If this variable
is unset or null, an unspecified default terminal type is
used.
Default.
The standard output shall be used to write the contents of the input
files.
The standard error shall be used for diagnostic messages and user
commands (see the INPUT FILES section), and, if standard output is a
terminal device, to write a prompting string. The prompting string
shall appear on the screen line below the last line of the file
displayed in the current screenful. The prompt shall contain the name
of the file currently being examined and shall contain an end-of-file
indication and the name of the next file, if any, when prompting at
the end-of-file. If an error or informational message is displayed,
it is unspecified whether it is contained in the prompt. If it is not
contained in the prompt, it shall be displayed and then the user
shall be prompted for a continuation character, at which point
another message or the user prompt may be displayed. The prompt is
otherwise unspecified. It is unspecified whether informational
messages are written for other user commands.
None.
The following section describes the behavior of more when the
standard output is a terminal device. If the standard output is not a
terminal device, no options other than −s shall have any effect, and
all input files shall be copied to standard output otherwise
unmodified, at which time more shall exit without further action.
The number of lines available per screen shall be determined by the
−n option, if present, or by examining values in the environment (see
the ENVIRONMENT VARIABLES section). If neither method yields a
number, an unspecified number of lines shall be used.
The maximum number of lines written shall be one less than this
number, because the screen line after the last line written shall be
used to write a user prompt and user input. If the number of lines in
the screen is less than two, the results are undefined. It is
unspecified whether user input is permitted to be longer than the
remainder of the single line where the prompt has been written.
The number of columns available per line shall be determined by
examining values in the environment (see the ENVIRONMENT VARIABLES
section), with a default value as described in the Base Definitions
volume of POSIX.1‐2008, Chapter 8, Environment Variables.
Lines that are longer than the display shall be folded; the length at
which folding occurs is unspecified, but should be appropriate for
the output device. Folding may occur between glyphs of single
characters that take up multiple display columns.
When standard output is a terminal and −u is not specified, more
shall treat <backspace> and <carriage-return> characters specially:
* A character, followed first by a sequence of n <backspace>
characters (where n is the same as the number of column positions
that the character occupies), then by n <underscore> characters
('_'), shall cause that character to be written as underlined
text, if the terminal type supports that. The n <underscore>
characters, followed first by n <backspace> characters, then any
character with n column positions, shall also cause that
character to be written as underlined text, if the terminal type
supports that.
* A sequence of n <backspace> characters (where n is the same as
the number of column positions that the previous character
occupies) that appears between two identical printable characters
shall cause the first of those two characters to be written as
emboldened text (that is, visually brighter, standout mode, or
inverse-video mode), if the terminal type supports that, and the
second to be discarded. Immediately subsequent occurrences of
<backspace>/character pairs for that same character shall also be
discarded. (For example, the sequence "a\ba\ba\ba" is interpreted
as a single emboldened 'a'.)
* The more utility shall logically discard all other <backspace>
characters from the line as well as the character which precedes
them, if any.
* A <carriage-return> at the end of a line shall be ignored, rather
than being written as a non-printable character, as described in
the next paragraph.
It is implementation-defined how other non-printable characters are
written. Implementations should use the same format that they use for
the ex print command; see the OPTIONS section within the ed utility.
It is unspecified whether a multi-column character shall be separated
if it crosses a display line boundary; it shall not be discarded. The
behavior is unspecified if the number of columns on the display is
less than the number of columns any single character in the line
being displayed would occupy.
When each new file is displayed (or redisplayed), more shall write
the first screen of the file. Once the initial screen has been
written, more shall prompt for a user command. If the execution of
the user command results in a screen that has lines in common with
the current screen, and the device has sufficient terminal
capabilities, more shall scroll the screen; otherwise, it is
unspecified whether the screen is scrolled or redrawn.
For all files but the last (including standard input if no file was
specified, and for the last file as well, if the −e option was not
specified), when more has written the last line in the file, more
shall prompt for a user command. This prompt shall contain the name
of the next file as well as an indication that more has reached end-
of-file. If the user command is f, <control>‐F, <space>, j,
<newline>, d, <control>‐D, or s, more shall display the next file.
Otherwise, if displaying the last file, more shall exit. Otherwise,
more shall execute the user command specified.
Several of the commands described in this section display a previous
screen from the input stream. In the case that text is being taken
from a non-rewindable stream, such as a pipe, it is implementation-
defined how much backwards motion is supported. If a command cannot
be executed because of a limitation on backwards motion, an error
message to this effect shall be displayed, the current screen shall
not change, and the user shall be prompted for another command.
If a command cannot be performed because there are insufficient lines
to display, more shall alert the terminal. If a command cannot be
performed because there are insufficient lines to display or a /
command fails: if the input is the standard input, the last screen in
the file may be displayed; otherwise, the current file and screen
shall not change, and the user shall be prompted for another command.
The interactive commands in the following sections shall be
supported. Some commands can be preceded by a decimal integer,
called count in the following descriptions. If not specified with the
command, count shall default to 1. In the following descriptions,
pattern is a basic regular expression, as described in the Base
Definitions volume of POSIX.1‐2008, Section 9.3, Basic Regular
Expressions. The term ``examine'' is historical usage meaning ``open
the file for viewing''; for example, more foo would be expressed as
examining file foo.
In the following descriptions, unless otherwise specified, line is a
line in the more display, not a line from the file being examined.
In the following descriptions, the current position refers to two
things:
1. The position of the current line on the screen
2. The line number (in the file) of the current line on the screen
Usually, the line on the screen corresponding to the current position
is the third line on the screen. If this is not possible (there are
fewer than three lines to display or this is the first page of the
file, or it is the last page of the file), then the current position
is either the first or last line on the screen as described later.
Help
Synopsis:
h
Write a summary of these commands and other implementation-defined
commands. The behavior shall be as if the more utility were executed
with the −e option on a file that contained the summary information.
The user shall be prompted as described earlier in this section when
end-of-file is reached. If the user command is one of those specified
to continue to the next file, more shall return to the file and
screen state from which the h command was executed.
Scroll Forward One Screenful
Synopsis:
[count]f
[count]<control>-F
Scroll forward count lines, with a default of one screenful. If count
is more than the screen size, only the final screenful shall be
written.
Scroll Backward One Screenful
Synopsis:
[count]b
[count]<control>-B
Scroll backward count lines, with a default of one screenful (see the
−n option). If count is more than the screen size, only the final
screenful shall be written.
Scroll Forward One Line
Synopsis:
[count]<space>
[count]j
[count]<newline>
Scroll forward count lines. The default count for the <space> shall
be one screenful; for j and <newline>, one line. The entire count
lines shall be written, even if count is more than the screen size.
Scroll Backward One Line
Synopsis:
[count]k
Scroll backward count lines. The entire count lines shall be written,
even if count is more than the screen size.
Scroll Forward One Half Screenful
Synopsis:
[count]d
[count]<control>-D
Scroll forward count lines, with a default of one half of the screen
size. If count is specified, it shall become the new default for
subsequent d, <control>‐D, and u commands.
Skip Forward One Line
Synopsis:
[count]s
Display the screenful beginning with the line count lines after the
last line on the current screen. If count would cause the current
position to be such that less than one screenful would be written,
the last screenful in the file shall be written.
Scroll Backward One Half Screenful
Synopsis:
[count]u
[count]<control>-U
Scroll backward count lines, with a default of one half of the screen
size. If count is specified, it shall become the new default for
subsequent d, <control>−D, u, and <control>−U commands. The entire
count lines shall be written, even if count is more than the screen
size.
Go to Beginning of File
Synopsis:
[count]g
Display the screenful beginning with line count.
Go to End-of-File
Synopsis:
[count]G
If count is specified, display the screenful beginning with the line
count. Otherwise, display the last screenful of the file.
Refresh the Screen
Synopsis:
r
<control>-L
Refresh the screen.
Discard and Refresh
Synopsis:
R
Refresh the screen, discarding any buffered input. If the current
file is non-seekable, buffered input shall not be discarded and the R
command shall be equivalent to the r command.
Mark Position
Synopsis:
mletter
Mark the current position with the letter named by letter, where
letter represents the name of one of the lowercase letters of the
portable character set. When a new file is examined, all marks may be
lost.
Return to Mark
Synopsis:
'letter
Return to the position that was previously marked with the letter
named by letter, making that line the current position.
Return to Previous Position
Synopsis:
''
Return to the position from which the last large movement command was
executed (where a ``large movement'' is defined as any movement of
more than a screenful of lines). If no such movements have been made,
return to the beginning of the file.
Search Forward for Pattern
Synopsis:
[count]/[!]pattern<newline>
Display the screenful beginning with the countth line containing the
pattern. The search shall start after the first line currently
displayed. The null regular expression ('/' followed by a <newline>)
shall repeat the search using the previous regular expression, with a
default count. If the character '!' is included, the matching lines
shall be those that do not contain the pattern. If no match is found
for the pattern, a message to that effect shall be displayed.
Search Backward for Pattern
Synopsis:
[count]?[!]pattern<newline>
Display the screenful beginning with the countth previous line
containing the pattern. The search shall start on the last line
before the first line currently displayed. The null regular
expression ('?' followed by a <newline>) shall repeat the search
using the previous regular expression, with a default count. If the
character '!' is included, matching lines shall be those that do not
contain the pattern. If no match is found for the pattern, a message
to that effect shall be displayed.
Repeat Search
Synopsis:
[count]n
Repeat the previous search for countth line containing the last
pattern (or not containing the last pattern, if the previous search
was "/!" or "?!").
Repeat Search in Reverse
Synopsis:
[count]N
Repeat the search in the opposite direction of the previous search
for the countth line containing the last pattern (or not containing
the last pattern, if the previous search was "/!" or "?!").
Examine New File
Synopsis:
:e [filename]<newline>
Examine a new file. If the filename argument is not specified, the
current file (see the :n and :p commands below) shall be re-examined.
The filename shall be subjected to the process of shell word
expansions (see Section 2.6, Word Expansions); if more than a single
pathname results, the effects are unspecified. If filename is a
<number-sign> ('#'), the previously examined file shall be re-
examined. If filename is not accessible for any reason (including
that it is a non-seekable file), an error message to this effect
shall be displayed and the current file and screen shall not change.
Examine Next File
Synopsis:
[count]:n
Examine the next file. If a number count is specified, the countth
next file shall be examined. If filename refers to a non-seekable
file, the results are unspecified.
Examine Previous File
Synopsis:
[count]:p
Examine the previous file. If a number count is specified, the
countth previous file shall be examined. If filename refers to a non-
seekable file, the results are unspecified.
Go to Tag
Synopsis:
:t tagstring<newline>
If the file containing the tag named by the tagstring argument is not
the current file, examine the file, as if the :e command was executed
with that file as the argument. Otherwise, or in addition, display
the screenful beginning with the tag, as described for the −t option
(see the OPTIONS section). If the ctags utility is not supported by
the system, the use of :t produces undefined results.
Invoke Editor
Synopsis:
v
Invoke an editor to edit the current file being examined. If standard
input is being examined, the results are unspecified. The name of the
editor shall be taken from the environment variable EDITOR, or shall
default to vi. If the last pathname component in EDITOR is either vi
or ex, the editor shall be invoked with a −c linenumber command line
argument, where linenumber is the line number of the file line
containing the display line currently displayed as the first line of
the screen. It is implementation-defined whether line-setting options
are passed to editors other than vi and ex.
When the editor exits, more shall resume with the same file and
screen as when the editor was invoked.
Display Position
Synopsis:
=
<control>-G
Write a message for which the information references the first byte
of the line after the last line of the file on the screen. This
message shall include the name of the file currently being examined,
its number relative to the total number of files there are to
examine, the line number in the file, the byte number and the total
bytes in the file, and what percentage of the file precedes the
current position. If more is reading from standard input, or the file
is shorter than a single screen, the line number, the byte number,
the total bytes, and the percentage need not be written.
Quit
Synopsis:
q
:q
ZZ
Exit more.
The following exit values shall be returned:
0 Successful completion.
>0 An error occurred.
If an error is encountered accessing a file when using the :n
command, more shall attempt to examine the next file in the argument
list, but the final exit status shall be affected. If an error is
encountered accessing a file via the :p command, more shall attempt
to examine the previous file in the argument list, but the final exit
status shall be affected. If an error is encountered accessing a file
via the :e command, more shall remain in the current file and the
final exit status shall not be affected.
The following sections are informative.
When the standard output is not a terminal, only the −s filter-
modification option is effective. This is based on historical
practice. For example, a typical implementation of man pipes its
output through more −s to squeeze excess white space for terminal
users. When man is piped to lp, however, it is undesirable for this
squeezing to happen.
The −p allows arbitrary commands to be executed at the start of each
file. Examples are:
more −p G file1 file2
Examine each file starting with its last screenful.
more −p 100 file1 file2
Examine each file starting with line 100 in the current
position (usually the third line, so line 98 would be the first
line written).
more −p /100 file1 file2
Examine each file starting with the first line containing the
string "100" in the current position
The more utility, available in BSD and BSD-derived systems, was
chosen as the prototype for the POSIX file display program since it
is more widely available than either the public-domain program less
or than pg, a pager provided in System V. The 4.4 BSD more is the
model for the features selected; it is almost fully upwards-
compatible from the 4.3 BSD version in wide use and has become more
amenable for vi users. Several features originally derived from
various file editors, found in both less and pg, have been added to
this volume of POSIX.1‐2008 as they have proved extremely popular
with users.
There are inconsistencies between more and vi that result from
historical practice. For example, the single-character commands h, f,
b, and <space> are screen movers in more, but cursor movers in vi.
These inconsistencies were maintained because the cursor movements
are not applicable to more and the powerful functionality achieved
without the use of the control key justifies the differences.
The tags interface has been included in a program that is not a text
editor because it promotes another degree of consistent operation
with vi. It is conceivable that the paging environment of more would
be superior for browsing source code files in some circumstances.
The operating mode referred to for block-mode terminals effectively
adds a <newline> to each Synopsis line that currently has none. So,
for example, d<newline> would page one screenful. The mode could be
triggered by a command line option, environment variable, or some
other method. The details are not imposed by this volume of
POSIX.1‐2008 because there are so few systems known to support such
terminals. Nevertheless, it was considered that all systems should be
able to support more given the exception cited for this small
community of terminals because, in comparison to vi, the cursor
movements are few and the command set relatively amenable to the
optional <newline> characters.
Some versions of more provide a shell escaping mechanism similar to
the ex ! command. The standard developers did not consider that this
was necessary in a paginator, particularly given the wide acceptance
of multiple window terminals and job control features. (They chose to
retain such features in the editors and mailx because the shell
interaction also gives an opportunity to modify the editing buffer,
which is not applicable to more.)
The −p (position) option replaces the + command because of the
Utility Syntax Guidelines. The +command option is no longer specified
by POSIX.1‐2008 but may be present in some implementations. In early
proposals, it took a pattern argument, but historical less provided
the more general facility of a command. It would have been desirable
to use the same −c as ex and vi, but the letter was already in use.
The text stating ``from a non-rewindable stream ... implementations
may limit the amount of backwards motion supported'' would allow an
implementation that permitted no backwards motion beyond text already
on the screen. It was not possible to require a minimum amount of
backwards motion that would be effective for all conceivable device
types. The implementation should allow the user to back up as far as
possible, within device and reasonable memory allocation constraints.
Historically, non-printable characters were displayed using the ARPA
standard mappings, which are as follows:
1. Printable characters are left alone.
2. Control characters less than \177 are represented as followed by
the character offset from the '@' character in the ASCII map; for
example, \007 is represented as 'G'.
3. \177 is represented as followed by '?'.
The display of characters having their eighth bit set was less
standard. Existing implementations use hex (0x00), octal (\000), and
a meta-bit display. (The latter displayed characters with their
eighth bit set as the two characters "M−", followed by the seven-bit
display as described previously.) The latter probably has the best
claim to historical practice because it was used with the −v option
of 4 BSD and 4 BSD-derived versions of the cat utility since 1980.
No specific display format is required by POSIX.1‐2008.
Implementations are encouraged to conform to historic practice in the
absence of any strong reason to diverge.
None.
Chapter 2, Shell Command Language, ctags(1p), ed(1p), ex(1p), vi(1p)
The Base Definitions volume of POSIX.1‐2008, Chapter 8, Environment
Variables, Section 9.2, Regular Expression General Requirements,
Section 9.3, Basic Regular Expressions, Section 12.2, Utility Syntax
Guidelines
Portions of this text are reprinted and reproduced in electronic form
from IEEE Std 1003.1, 2013 Edition, Standard for Information
Technology -- Portable Operating System Interface (POSIX), The Open
Group Base Specifications Issue 7, Copyright (C) 2013 by the
Institute of Electrical and Electronics Engineers, Inc and The Open
Group. (This is POSIX.1-2008 with the 2013 Technical Corrigendum 1
applied.) In the event of any discrepancy between this version and
the original IEEE and The Open Group Standard, the original IEEE and
The Open Group Standard is the referee document. The original
Standard can be obtained online at http://www.unix.org/online.html .
Any typographical or formatting errors that appear in this page are
most likely to have been introduced during the conversion of the
source files to man page format. To report such errors, see
https://www.kernel.org/doc/man-pages/reporting_bugs.html .
IEEE/The Open Group 2013 MORE(1P)
Pages that refer to this page: cat(1p), mailx(1p), man(1p)