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Diff for /src/usr.bin/less/Attic/less.nro between version 1.1.1.2 and 1.1.1.3

version 1.1.1.2, 2003/04/13 18:21:21

version 1.1.1.3, 2011/09/16 17:47:06

Line 1

.TH LESS 1 "Version 381: 17 Jan 2003"

.TH LESS 1 "Version 444: 09 Jun 2011"

.SH NAME

less \- opposite of more

.SH SYNOPSIS

.B "less -?"

.B "less \-?"

.br

.B "less --help"

.B "less \-\-help"

.br

.B "less -V"

.B "less \-V"

.br

.B "less --version"

.B "less \-\-version"

.br

.B "less [-[+]aBcCdeEfFgGiIJLmMnNqQrRsSuUVwWX~]"

.B "less [\-[+]aABcCdeEfFgGiIJKLmMnNqQrRsSuUVwWX~]"

.br

.B " [-b \fIspace\fP] [-h \fIlines\fP] [-j \fIline\fP] [-k \fIkeyfile\fP]"

.B " [\-b \fIspace\fP] [\-h \fIlines\fP] [\-j \fIline\fP] [\-k \fIkeyfile\fP]"

.br

.B " [-{oO} \fIlogfile\fP] [-p \fIpattern\fP] [-P \fIprompt\fP] [-t \fItag\fP]"

.B " [\-{oO} \fIlogfile\fP] [\-p \fIpattern\fP] [\-P \fIprompt\fP] [\-t \fItag\fP]"

.br

.B " [-T \fItagsfile\fP] [-x \fItab\fP,...] [-y \fIlines\fP] [-[z] \fIlines\fP]"

.B " [\-T \fItagsfile\fP] [\-x \fItab\fP,...] [\-y \fIlines\fP] [\-[z] \fIlines\fP]"

.br

.B " [-# \fIshift\fP] [+[+]\fIcmd\fP] [--] [\fIfilename\fP]..."

.B " [\-# \fIshift\fP] [+[+]\fIcmd\fP] [\-\-] [\fIfilename\fP]..."

.br

(See the OPTIONS section for alternate option syntax with long option names.)

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Help: display a summary of these commands.

If you forget all the other commands, remember this one.

.IP "SPACE or ^V or f or ^F"

Scroll forward N lines, default one window (see option -z below).

Scroll forward N lines, default one window (see option \-z below).

If N is more than the screen size, only the final screenful is displayed.

Warning: some systems use ^V as a special literalization character.

.IP "z"

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.IP "ESC-SPACE"

Like SPACE, but scrolls a full screenful, even if it reaches

end-of-file in the process.

.IP "RETURN or ^N or e or ^E or j or ^J"

.IP "ENTER or RETURN or ^N or e or ^E or j or ^J"

Scroll forward N lines, default 1.

The entire N lines are displayed, even if N is more than the screen size.

.IP "d or ^D"

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If N is specified, it becomes the new default for

subsequent d and u commands.

.IP "b or ^B or ESC-v"

Scroll backward N lines, default one window (see option -z below).

Scroll backward N lines, default one window (see option \-z below).

If N is more than the screen size, only the final screenful is displayed.

.IP "w"

Like ESC-v, but if N is specified, it becomes the new window size.

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subsequent d and u commands.

.IP "ESC-) or RIGHTARROW"

Scroll horizontally right N characters, default half the screen width

(see the -# option).

(see the \-# option).

If a number N is specified, it becomes the default for future RIGHTARROW

and LEFTARROW commands.

While the text is scrolled, it acts as though the -S option

While the text is scrolled, it acts as though the \-S option

(chop lines) were in effect.

.IP "ESC-( or LEFTARROW"

Scroll horizontally left N characters, default half the screen width

(see the -# option).

(see the \-# option).

If a number N is specified, it becomes the default for future RIGHTARROW

and LEFTARROW commands.

.IP "r or ^R or ^L"

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Normally this command would be used when already at the end of the file.

It is a way to monitor the tail of a file which is growing

while it is being viewed.

(The behavior is similar to the "tail -f" command.)

(The behavior is similar to the "tail \-f" command.)

.IP "g or < or ESC-<"

Go to line N in the file, default 1 (beginning of file).

(Warning: this may be slow if N is large.)

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standard input, rather than a file, is being read.)

.IP "p or %"

Go to a position N percent into the file.

N should be between 0 and 100.

N should be between 0 and 100, and may contain a decimal point.

.IP "P"

Go to the line containing byte offset N in the file.

.IP "{"

If a left curly bracket appears in the top line displayed

on the screen,

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Search forward in the file for the N-th line containing the pattern.

N defaults to 1.

The pattern is a regular expression, as recognized by

.I ed.

the regular expression library supplied by your system.

The search starts at the second line displayed

The search starts at the first line displayed

(but see the -a and -j options, which change this).

(but see the \-a and \-j options, which change this).

.sp

Certain characters are special

if entered at the beginning of the pattern;

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Begin the search at the first line of the FIRST file

in the command line list,

regardless of what is currently displayed on the screen

or the settings of the -a or -j options.

or the settings of the \-a or \-j options.

.IP "^K"

Highlight any text which matches the pattern on the current screen,

but don't move to the first match (KEEP current position).

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Begin the search at the last line of the last file

in the command line list,

regardless of what is currently displayed on the screen

or the settings of the -a or -j options.

or the settings of the \-a or \-j options.

.IP "^K"

As in forward searches.

.IP "^R"

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If highlighting is already off because of a previous ESC-u command,

turn highlighting back on.

Any search command will also turn highlighting back on.

(Highlighting can also be disabled by toggling the -G option;

(Highlighting can also be disabled by toggling the \-G option;

in that case search commands do not turn highlighting back on.)

.IP "&pattern"

Display only lines which match the pattern;

lines which do not match the pattern are not displayed.

If pattern is empty (if you type & immediately followed by ENTER),

any filtering is turned off, and all lines are displayed.

While filtering is in effect, an ampersand is displayed at the

beginning of the prompt,

as a reminder that some lines in the file may be hidden.

.sp

Certain characters are special as in the / command:

.RS

.IP "^N or !"

Display only lines which do NOT match the pattern.

.IP "^R"

Don't interpret regular expression metacharacters;

that is, do a simple textual comparison.

.RE

.IP ":e [filename]"

Examine a new file.

If the filename is missing, the "current" file (see the :n and :p commands

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the list of files and the first one is examined.

If the filename contains one or more spaces,

the entire filename should be enclosed in double quotes

(also see the -" option).

(also see the \-" option).

.IP "^X^V or E"

Same as :e.

Warning: some systems use ^V as a special literalization character.

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and print a message describing the new setting.

If a ^P (CONTROL-P) is entered immediately after the dash,

the setting of the option is changed but no message is printed.

If the option letter has a numeric value (such as -b or -h),

If the option letter has a numeric value (such as \-b or \-h),

or a string value (such as -P or -t),

or a string value (such as \-P or \-t),

a new value may be entered after the option letter.

If no new value is entered, a message describing

the current setting is printed and nothing is changed.

.IP \-\-

Like the \- command, but takes a long option name (see OPTIONS below)

rather than a single option letter.

You must press RETURN after typing the option name.

You must press ENTER or RETURN after typing the option name.

A ^P immediately after the second dash suppresses printing of a

message describing the new setting, as in the \- command.

.IP \-+

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(Double underscore.)

Like the _ (underscore) command, but takes a long option name

rather than a single option letter.

You must press RETURN after typing the option name.

You must press ENTER or RETURN after typing the option name.

.IP +cmd

Causes the specified cmd to be executed each time a new file is examined.

For example, +G causes

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or two dashes followed by a long option name.

A long option name may be abbreviated as long as

the abbreviation is unambiguous.

For example, --quit-at-eof may be abbreviated --quit, but not

For example, \-\-quit-at-eof may be abbreviated \-\-quit, but not

--qui, since both --quit-at-eof and --quiet begin with --qui.

--qui, since both \-\-quit-at-eof and \-\-quiet begin with \-\-qui.

Some long option names are in uppercase, such as --QUIT-AT-EOF, as

Some long option names are in uppercase, such as \-\-QUIT-AT-EOF, as

distinct from --quit-at-eof.

distinct from \-\-quit-at-eof.

Such option names need only have their first letter capitalized;

the remainder of the name may be in either case.

For example, --Quit-at-eof is equivalent to --QUIT-AT-EOF.

For example, \-\-Quit-at-eof is equivalent to \-\-QUIT-AT-EOF.

.PP

Options are also taken from the environment variable "LESS".

For example,

to avoid typing "less -options ..." each time

to avoid typing "less \-options ..." each time

.I less

is invoked, you might tell

.I csh:

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to its default value on the command line by beginning the command

line option with "\-+".

.sp

For options like -P or -D which take a following string,

For options like \-P or \-D which take a following string,

a dollar sign ($) must be used to signal the end of the string.

For example, to set two -D options on MS-DOS, you must have

For example, to set two \-D options on MS-DOS, you must have

a dollar sign between them, like this:

.sp

LESS="-Dn9.1$-Ds4.1"

.sp

.IP "-? or --help"

.IP "\-? or \-\-help"

This option displays a summary of the commands accepted by

.I less

(the same as the h command).

(Depending on how your shell interprets the question mark,

it may be necessary to quote the question mark, thus: "-\e?".)

it may be necessary to quote the question mark, thus: "\-\e?".)

.IP "-a or --search-skip-screen"

.IP "\-a or \-\-search-skip-screen"

Causes searches to start after the last line

By default, forward searches start at the top of the displayed screen

displayed on the screen,

and backwards searches start at the bottom of the displayed screen

(except for repeated searches invoked by the n or N commands,

which start after or before the "target" line respectively;

see the \-j option for more about the target line).

The \-a option causes forward searches to instead start at

the bottom of the screen

and backward searches to start at the top of the screen,

thus skipping all lines displayed on the screen.

By default, searches start at the second line on the screen

.IP "\-A or \-\-SEARCH-SKIP-SCREEN"

(or after the last found line; see the -j option).

Causes all forward searches (not just non-repeated searches)

.IP "-b\fIn\fP or --buffers=\fIn\fP"

to start just after the target line, and all backward searches

to start just before the target line.

Thus, forward searches will skip part of the displayed screen

(from the first line up to and including the target line).

Similarly backwards searches will skip the displayed screen

from the last line up to and including the target line.

This was the default behavior in less versions prior to 441.

.IP "\-b\fIn\fP or \-\-buffers=\fIn\fP"

Specifies the amount of buffer space

.I less

will use for each file, in units of kilobytes (1024 bytes).

By default 64K of buffer space is used for each file

(unless the file is a pipe; see the -B option).

(unless the file is a pipe; see the \-B option).

The -b option specifies instead that \fIn\fP kilobytes of

The \-b option specifies instead that \fIn\fP kilobytes of

buffer space should be used for each file.

If \fIn\fP is -1, buffer space is unlimited; that is,

If \fIn\fP is \-1, buffer space is unlimited; that is,

the entire file is read into memory.

the entire file can be read into memory.

.IP "-B or --auto-buffers"

.IP "\-B or \-\-auto-buffers"

By default, when data is read from a pipe,

buffers are allocated automatically as needed.

If a large amount of data is read from the pipe, this can cause

a large amount of memory to be allocated.

The -B option disables this automatic allocation of buffers for pipes,

The \-B option disables this automatic allocation of buffers for pipes,

so that only 64K

(or the amount of space specified by the -b option)

(or the amount of space specified by the \-b option)

is used for the pipe.

Warning: use of -B can result in erroneous display, since only the

Warning: use of \-B can result in erroneous display, since only the

most recently viewed part of the file is kept in memory;

most recently viewed part of the piped data is kept in memory;

any earlier data is lost.

.IP "-c or --clear-screen"

.IP "\-c or \-\-clear-screen"

Causes full screen repaints to be painted from the top line down.

By default,

full screen repaints are done by scrolling from the bottom of the screen.

.IP "-C or --CLEAR-SCREEN"

.IP "\-C or \-\-CLEAR-SCREEN"

The -C option is like -c, but the screen is cleared before it is repainted.

Same as \-c, for compatibility with older versions of

.IP "-d or --dumb"

.I less.

The -d option suppresses the error message

.IP "\-d or \-\-dumb"

The \-d option suppresses the error message

normally displayed if the terminal is dumb;

that is, lacks some important capability,

such as the ability to clear the screen or scroll backward.

The -d option does not otherwise change the behavior of

The \-d option does not otherwise change the behavior of

.I less

on a dumb terminal.

.IP "-D\fBx\fP\fIcolor\fP or --color=\fBx\fP\fIcolor\fP"

.IP "\-D\fBx\fP\fIcolor\fP or \-\-color=\fBx\fP\fIcolor\fP"

[MS-DOS only]

Sets the color of the text displayed.

\fBx\fP is a single character which selects the type of text whose color is

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\fIcolor\fP is a pair of numbers separated by a period.

The first number selects the foreground color and the second selects

the background color of the text.

A single number \fIN\fP is the same as \fIN.0\fP.

A single number \fIN\fP is the same as \fIN.M\fP,

.IP "-e or --quit-at-eof"

where \fIM\fP is the normal background color.

.IP "\-e or \-\-quit-at-eof"

Causes

.I less

to automatically exit

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By default, the only way to exit

.I less

is via the "q" command.

.IP "-E or --QUIT-AT-EOF"

.IP "\-E or \-\-QUIT-AT-EOF"

Causes

.I less

to automatically exit the first time it reaches end-of-file.

.IP "-f or --force"

.IP "\-f or \-\-force"

Forces non-regular files to be opened.

(A non-regular file is a directory or a device special file.)

Also suppresses the warning message when a binary file is opened.

By default,

.I less

will refuse to open non-regular files.

.IP "-F or --quit-if-one-screen"

Note that some operating systems will not allow directories

to be read, even if \-f is set.

.IP "\-F or \-\-quit-if-one-screen"

Causes

.I less

to automatically exit

if the entire file can be displayed on the first screen.

.IP "-g or --hilite-search"

.IP "\-g or \-\-hilite-search"

Normally,

.I less

will highlight ALL strings which match the last search command.

The -g option changes this behavior to highlight only the particular string

The \-g option changes this behavior to highlight only the particular string

which was found by the last search command.

This can cause

.I less

to run somewhat faster than the default.

.IP "-G or --HILITE-SEARCH"

.IP "\-G or \-\-HILITE-SEARCH"

The -G option suppresses all highlighting of strings found by search commands.

The \-G option suppresses all highlighting of strings found by search commands.

.IP "-h\fIn\fP or ---max-back-scroll=\fIn\fP"

.IP "\-h\fIn\fP or \-\-max-back-scroll=\fIn\fP"

Specifies a maximum number of lines to scroll backward.

If it is necessary to scroll backward more than \fIn\fP lines,

the screen is repainted in a forward direction instead.

(If the terminal does not have the ability to scroll

backward, -h0 is implied.)

backward, \-h0 is implied.)

.IP "-i or --ignore-case"

.IP "\-i or \-\-ignore-case"

Causes searches to ignore case; that is,

uppercase and lowercase are considered identical.

This option is ignored if any uppercase letters

appear in the search pattern;

in other words,

if a pattern contains uppercase letters, then that search does not ignore case.

.IP "-I or --IGNORE-CASE"

.IP "\-I or \-\-IGNORE-CASE"

Like -i, but searches ignore case even if

Like \-i, but searches ignore case even if

the pattern contains uppercase letters.

.IP "-j\fIn\fP or --jump-target=\fIn\fP"

.IP "\-j\fIn\fP or \-\-jump-target=\fIn\fP"

Specifies a line on the screen where the "target" line

is to be positioned.

A target line is the object of a text search,

The target line is the line specified by any command to

tag search, jump to a line number,

search for a pattern, jump to a line number,

jump to a file percentage, or jump to a marked position.

jump to a file percentage or jump to a tag.

The screen line is specified by a number: the top line on the screen

The screen line may be specified by a number: the top line on the screen

is 1, the next is 2, and so on.

The number may be negative to specify a line relative to the bottom

of the screen: the bottom line on the screen is -1, the second

of the screen: the bottom line on the screen is \-1, the second

to the bottom is -2, and so on.

to the bottom is \-2, and so on.

If the -j option is used, searches begin at the line immediately

Alternately, the screen line may be specified as a fraction of the height

after the target line.

of the screen, starting with a decimal point: .5 is in the middle of the

For example, if "-j4" is used, the target line is the

screen, .3 is three tenths down from the first line, and so on.

fourth line on the screen, so searches begin at the fifth line

If the line is specified as a fraction, the actual line number

is recalculated if the terminal window is resized, so that the

target line remains at the specified fraction of the screen height.

If any form of the \-j option is used,

forward searches begin at the line immediately after the target line,

and backward searches begin at the target line,

unless changed by \-a or \-A.

For example, if "\-j4" is used, the target line is the

fourth line on the screen, so forward searches begin at the fifth line

on the screen.

.IP "-J or --status-column"

.IP "\-J or \-\-status-column"

Displays a status column at the left edge of the screen.

The status column shows the lines that matched the current search.

The status column is also used if the -w or -W option is in effect.

The status column is also used if the \-w or \-W option is in effect.

.IP "-k\fIfilename\fP or --lesskey-file=\fIfilename\fP"

.IP "\-k\fIfilename\fP or \-\-lesskey-file=\fIfilename\fP"

Causes

.I less

to open and interpret the named file as a

.I lesskey

(1) file.

Multiple -k options may be specified.

Multiple \-k options may be specified.

If the LESSKEY or LESSKEY_SYSTEM environment variable is set, or

if a lesskey file is found in a standard place (see KEY BINDINGS),

it is also used as a

.I lesskey

file.

.IP "-L or --no-lessopen"

.IP "\-K or \-\-quit-on-intr"

Causes

.I less

to exit immediately (with status 2)

when an interrupt character (usually ^C) is typed.

Normally, an interrupt character causes

.I less

to stop whatever it is doing and return to its command prompt.

Note that use of this option makes it impossible to return to the

command prompt from the "F" command.

.IP "\-L or \-\-no-lessopen"

Ignore the LESSOPEN environment variable

(see the INPUT PREPROCESSOR section below).

This option can be set from within \fIless\fP,

but it will apply only to files opened subsequently, not to the

file which is currently open.

.IP "-m or --long-prompt"

.IP "\-m or \-\-long-prompt"

Causes

.I less

to prompt verbosely (like \fImore\fP),

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By default,

.I less

prompts with a colon.

.IP "-M or --LONG-PROMPT"

.IP "\-M or \-\-LONG-PROMPT"

Causes

.I less

to prompt even more verbosely than

.I more.

.IP "-n or --line-numbers"

.IP "\-n or \-\-line-numbers"

Suppresses line numbers.

The default (to use line numbers) may cause

.I less

to run more slowly in some cases, especially with a very large input file.

Suppressing line numbers with the -n option will avoid this problem.

Suppressing line numbers with the \-n option will avoid this problem.

Using line numbers means: the line number will be displayed in the verbose

prompt and in the = command,

and the v command will pass the current line number to the editor

(see also the discussion of LESSEDIT in PROMPTS below).

.IP "-N or --LINE-NUMBERS"

.IP "\-N or \-\-LINE-NUMBERS"

Causes a line number to be displayed at the beginning of

each line in the display.

.IP "-o\fIfilename\fP or --log-file=\fIfilename\fP"

.IP "\-o\fIfilename\fP or \-\-log-file=\fIfilename\fP"

Causes

.I less

to copy its input to the named file as it is being viewed.

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If the file already exists,

.I less

will ask for confirmation before overwriting it.

.IP "-O\fIfilename\fP or --LOG-FILE=\fIfilename\fP"

.IP "\-O\fIfilename\fP or \-\-LOG-FILE=\fIfilename\fP"

The -O option is like -o, but it will overwrite an existing

The \-O option is like \-o, but it will overwrite an existing

file without asking for confirmation.

.sp

If no log file has been specified,

the -o and -O options can be used from within

the \-o and \-O options can be used from within

.I less

to specify a log file.

Without a file name, they will simply report the name of the log file.

The "s" command is equivalent to specifying -o from within

The "s" command is equivalent to specifying \-o from within

.I less.

.IP "-p\fIpattern\fP or --pattern=\fIpattern\fP"

.IP "\-p\fIpattern\fP or \-\-pattern=\fIpattern\fP"

The -p option on the command line is equivalent to

The \-p option on the command line is equivalent to

specifying +/\fIpattern\fP;

that is, it tells

.I less

to start at the first occurrence of \fIpattern\fP in the file.

.IP "-P\fIprompt\fP or --prompt=\fIprompt\fP"

.IP "\-P\fIprompt\fP or \-\-prompt=\fIprompt\fP"

Provides a way to tailor the three prompt

styles to your own preference.

This option would normally be put in the LESS environment

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or be terminated by a dollar sign.

-Ps followed by a string changes the default (short) prompt

to that string.

-Pm changes the medium (-m) prompt.

-Pm changes the medium (\-m) prompt.

-PM changes the long (-M) prompt.

-PM changes the long (\-M) prompt.

-Ph changes the prompt for the help screen.

-P= changes the message printed by the = command.

-Pw changes the message printed while waiting for data (in the F command).

All prompt strings consist of a sequence of

letters and special escape sequences.

See the section on PROMPTS for more details.

.IP "-q or --quiet or --silent"

.IP "\-q or \-\-quiet or \-\-silent"

Causes moderately "quiet" operation:

the terminal bell is not rung

if an attempt is made to scroll past the end of the file

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The bell will be rung on certain other errors,

such as typing an invalid character.

The default is to ring the terminal bell in all such cases.

.IP "-Q or --QUIET or --SILENT"

.IP "\-Q or \-\-QUIET or \-\-SILENT"

Causes totally "quiet" operation:

the terminal bell is never rung.

.IP "-r or --raw-control-chars"

.IP "\-r or \-\-raw-control-chars"

Causes "raw" control characters to be displayed.

The default is to display control characters using the caret notation;

for example, a control-A (octal 001) is displayed as "^A".

Warning: when the -r option is used,

Warning: when the \-r option is used,

.I less

cannot keep track of the actual appearance of the screen

(since this depends on how the screen responds to

each type of control character).

Thus, various display problems may result,

such as long lines being split in the wrong place.

.IP "-R or --RAW-CONTROL-CHARS"

.IP "\-R or \-\-RAW-CONTROL-CHARS"

Like -r, but tries to keep track of the screen appearance where possible.

Like \-r, but only ANSI "color" escape sequences are output in "raw" form.

This works only if the input consists of normal text and possibly some

Unlike \-r, the screen appearance is maintained correctly in most cases.

ANSI "color" escape sequences, which are sequences of the form:

ANSI "color" escape sequences are sequences of the form:

.sp

ESC [ ... m

.sp

where the "..." is zero or more characters other than "m".

where the "..." is zero or more color specification characters

For the purpose of keeping track of screen appearance,

all control characters and all ANSI color escape sequences are

ANSI color escape sequences are assumed to not move the cursor.

assumed to not move the cursor.

You can make

.I less

think that characters other than "m" can end ANSI color escape sequences

by setting the environment variable LESSANSIENDCHARS to the list of

characters which can end a color escape sequence.

.IP "-s or --squeeze-blank-lines"

And you can make

.I less

think that characters other than the standard ones may appear between

the ESC and the m by setting the environment variable LESSANSIMIDCHARS

to the list of characters which can appear.

.IP "\-s or \-\-squeeze-blank-lines"

Causes consecutive blank lines to be squeezed into a single blank line.

This is useful when viewing

.I nroff

output.

.IP "-S or --chop-long-lines"

.IP "\-S or \-\-chop-long-lines"

Causes lines longer than the screen width to be

chopped rather than folded.

That is, the portion of a long line that does not fit in

the screen width is not shown.

The default is to fold long lines; that is, display the remainder

on the next line.

.IP "-t\fItag\fP or --tag=\fItag\fP"

.IP "\-t\fItag\fP or \-\-tag=\fItag\fP"

The -t option, followed immediately by a TAG,

The \-t option, followed immediately by a TAG,

will edit the file containing that tag.

For this to work, tag information must be available;

for example, there may be a file in the current directory called "tags",

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.I global

(1), and that command is executed to find the tag.

(See http://www.gnu.org/software/global/global.html).

The -t option may also be specified from within

The \-t option may also be specified from within

.I less

(using the \- command) as a way of examining a new file.

The command ":t" is equivalent to specifying -t from within

The command ":t" is equivalent to specifying \-t from within

.I less.

.IP "-T\fItagsfile\fP or --tag-file=\fItagsfile\fP"

.IP "\-T\fItagsfile\fP or \-\-tag-file=\fItagsfile\fP"

Specifies a tags file to be used instead of "tags".

.IP "-u or --underline-special"

.IP "\-u or \-\-underline-special"

Causes backspaces and carriage returns to be treated as printable characters;

that is, they are sent to the terminal when they appear in the input.

.IP "-U or --UNDERLINE-SPECIAL"

.IP "\-U or \-\-UNDERLINE-SPECIAL"

Causes backspaces, tabs and carriage returns to be

treated as control characters;

that is, they are handled as specified by the -r option.

that is, they are handled as specified by the \-r option.

.sp

By default, if neither -u nor -U is given,

By default, if neither \-u nor \-U is given,

backspaces which appear adjacent to an underscore character

are treated specially:

the underlined text is displayed

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using the terminal's hardware boldface capability.

Other backspaces are deleted, along with the preceding character.

Carriage returns immediately followed by a newline are deleted.

other carriage returns are handled as specified by the -r option.

other carriage returns are handled as specified by the \-r option.

Text which is overstruck or underlined can be searched for

if neither -u nor -U is in effect.

if neither \-u nor \-U is in effect.

.IP "-V or --version"

.IP "\-V or \-\-version"

Displays the version number of

.I less.

.IP "-w or --hilite-unread"

.IP "\-w or \-\-hilite-unread"

Temporarily highlights the first "new" line after a forward movement

of a full page.

The first "new" line is the line immediately following the line previously

at the bottom of the screen.

Also highlights the target line after a g or p command.

The highlight is removed at the next command which causes movement.

The entire line is highlighted, unless the -J option is in effect,

The entire line is highlighted, unless the \-J option is in effect,

in which case only the status column is highlighted.

.IP "-W or --HILITE-UNREAD"

.IP "\-W or \-\-HILITE-UNREAD"

Like -w, but temporarily highlights the first new line after any

Like \-w, but temporarily highlights the first new line after any

forward movement command larger than one line.

.IP "-x\fIn\fP,... or --tabs=\fIn\fP,..."

.IP "\-x\fIn\fP,... or \-\-tabs=\fIn\fP,..."

Sets tab stops.

If only one \fIn\fP is specified, tab stops are set at multiples of \fIn\fP.

If multiple values separated by commas are specified, tab stops

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last two.

For example, \fI-x9,17\fP will set tabs at positions 9, 17, 25, 33, etc.

The default for \fIn\fP is 8.

.IP "-X or --no-init"

.IP "\-X or \-\-no-init"

Disables sending the termcap initialization and deinitialization strings

to the terminal.

This is sometimes desirable if the deinitialization string does

something unnecessary, like clearing the screen.

.IP "--no-keypad"

.IP "\-y\fIn\fP or \-\-max-forw-scroll=\fIn\fP"

Disables sending the keypad initialization and deinitialization strings

to the terminal.

This is sometimes useful if the keypad strings make the numeric

keypad behave in an undesirable manner.

.IP "-y\fIn\fP or --max-forw-scroll=\fIn\fP"

Specifies a maximum number of lines to scroll forward.

If it is necessary to scroll forward more than \fIn\fP lines,

the screen is repainted instead.

The -c or -C option may be used to repaint from the top of

The \-c or \-C option may be used to repaint from the top of

the screen if desired.

By default, any forward movement causes scrolling.

.IP "-[z]\fIn\fP or --window=\fIn\fP"

.IP "\-[z]\fIn\fP or \-\-window=\fIn\fP"

Changes the default scrolling window size to \fIn\fP lines.

The default is one screenful.

The z and w commands can also be used to change the window size.

The "z" may be omitted for compatibility with

The "z" may be omitted for compatibility with some versions of

.I more.

If the number

.I n

is negative, it indicates

.I n

lines less than the current screen size.

For example, if the screen is 24 lines, \fI-z-4\fP sets the

For example, if the screen is 24 lines, \fI\-z-4\fP sets the

scrolling window to 20 lines. If the screen is resized to 40 lines,

the scrolling window automatically changes to 36 lines.

.IP "-\fI\(dqcc\fP\ or\ --quotes=\fIcc\fP"

.IP "\-\fI\(dqcc\fP\ or\ \-\-quotes=\fIcc\fP"

Changes the filename quoting character.

This may be necessary if you are trying to name a file

which contains both spaces and quote characters.

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Filenames containing a space should then be preceded by the open quote

character and followed by the close quote character.

Note that even after the quote characters are changed, this option

remains -" (a dash followed by a double quote).

remains \-" (a dash followed by a double quote).

.IP "-~ or --tilde"

.IP "\-~ or \-\-tilde"

Normally lines after end of file are displayed as a single tilde (~).

This option causes lines after end of file to be displayed as blank lines.

.IP "-# or --shift"

.IP "\-# or \-\-shift"

Specifies the default number of positions to scroll horizontally

in the RIGHTARROW and LEFTARROW commands.

If the number specified is zero, it sets the default number of

positions to one half of the screen width.

.IP --

Alternately, the number may be specified as a fraction of the width

A command line argument of "--" marks the end of option arguments.

of the screen, starting with a decimal point: .5 is half of the

screen width, .3 is three tenths of the screen width, and so on.

If the number is specified as a fraction, the actual number of

scroll positions is recalculated if the terminal window is resized,

so that the actual scroll remains at the specified fraction

of the screen width.

.IP "\-\-no-keypad"

Disables sending the keypad initialization and deinitialization strings

to the terminal.

This is sometimes useful if the keypad strings make the numeric

keypad behave in an undesirable manner.

.IP "\-\-follow-name"

Normally, if the input file is renamed while an F command is executing,

.I less

will continue to display the contents of the original file despite

its name change.

If \-\-follow-name is specified, during an F command

.I less

will periodically attempt to reopen the file by name.

If the reopen succeeds and the file is a different file from the original

(which means that a new file has been created

with the same name as the original (now renamed) file),

.I less

will display the contents of that new file.

.IP \-\-

A command line argument of "\-\-" marks the end of option arguments.

Any arguments following this are interpreted as filenames.

This can be useful when viewing a file whose name begins with a "-" or "+".

This can be useful when viewing a file whose name begins with a "\-" or "+".

.IP +

If a command line option begins with \fB+\fP,

the remainder of that option is taken to be an initial command to

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certain keys can be used to manipulate the command line.

Most commands have an alternate form in [ brackets ] which can be used if

a key does not exist on a particular keyboard.

(The bracketed forms do not work in the MS-DOS version.)

(Note that the forms beginning with ESC do not work

in some MS-DOS and Windows systems because ESC is the line erase character.)

Any of these special keys may be entered literally by preceding

it with the "literal" character, either ^V or ^A.

A backslash itself may also be entered literally by entering two backslashes.

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or cancel the command if the command line is empty.

If you have changed your line-kill character in Unix to something

other than ^U, that character is used instead of ^U.

.IP "^G"

Delete the entire command line and return to the main prompt.

.SH "KEY BINDINGS"

You may define your own

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.br

case "$1" in

.br

*.Z) uncompress -c $1 >/tmp/less.$$ 2>/dev/null

*.Z) uncompress -\c $1 >/tmp/less.$$ 2>/dev/null

.br

if [ -s /tmp/less.$$ ]; then

if [ \-s /tmp/less.$$ ]; then

.br

echo /tmp/less.$$

.br

else

.br

rm -f /tmp/less.$$

rm \-f /tmp/less.$$

.br

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.br

case "$1" in

.br

*.Z) uncompress -c $1 2>/dev/null

*.Z) uncompress \-c $1 2>/dev/null

.br

;;

.br

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but it is usually not necessary since there is no replacement file

to clean up.

In this case, the replacement file name passed to the LESSCLOSE

postprocessor is "-".

postprocessor is "\-".

.PP

For compatibility with previous versions of

.I less,

the input preprocessor or pipe is not used if

.I less

is viewing standard input.

However, if the first character of LESSOPEN is a dash (\-),

the input preprocessor is used on standard input as well as other files.

In this case, the dash is not considered to be part of

the preprocessor command.

If standard input is being viewed, the input preprocessor is passed

a file name consisting of a single dash.

Similarly, if the first two characters of LESSOPEN are vertical bar and dash

(|\-), the input pipe is used on standard input as well as other files.

Again, in this case the dash is not considered to be part of

the input pipe command.

.SH "NATIONAL CHARACTER SETS"

There are three types of characters in the input file:

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Selects a character set appropriate for NeXT computers.

.IP utf-8

Selects the UTF-8 encoding of the ISO 10646 character set.

UTF-8 is special in that it supports multi-byte characters in the input file.

It is the only character set that supports multi-byte characters.

.IP windows

Selects a character set appropriate for Microsoft Windows (cp 1251).

.PP

In special cases, it may be desired to tailor

In rare cases, it may be desired to tailor

.I less

to use a character set other than the ones definable by LESSCHARSET.

In this case, the environment variable LESSCHARDEF can be used

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next\ \ 8bcccbcc18b95.bb125.bb

.PP

If neither LESSCHARSET nor LESSCHARDEF is set,

but the string "UTF-8" is found in the LC_ALL, LC_TYPE or LANG

but any of the strings "UTF-8", "UTF8", "utf-8" or "utf8"

is found in the LC_ALL, LC_CTYPE or LANG

environment variables, then the default character set is utf-8.

.PP

If that string is not found, but your system supports the

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printf-style escape sequence (a % followed by x, X, o, d, etc.).

For example, if LESSBINFMT is "*u[%x]", binary characters

are displayed in underlined hexadecimal surrounded by brackets.

The default if no LESSBINFMT is specified is "*s<%X>".

The default if no LESSBINFMT is specified is "*s<%02X>".

Warning: the result of expanding the character via LESSBINFMT must

be less than 31 characters.

.PP

When the character set is utf-8, the LESSUTFBINFMT environment variable

acts similarly to LESSBINFMT but it applies to Unicode code points

that were successfully decoded but are unsuitable for display (e.g.,

unassigned code points).

Its default value is "<U+%04lX>".

Note that LESSUTFBINFMT and LESSBINFMT share their display attribute

setting ("*x") so specifying one will affect both;

LESSUTFBINFMT is read after LESSBINFMT so its setting, if any,

will have priority.

Problematic octets in a UTF-8 file (octets of a truncated sequence,

octets of a complete but non-shortest form sequence, illegal octets,

and stray trailing octets)

are displayed individually using LESSBINFMT so as to facilitate diagnostic

of how the UTF-8 file is ill-formed.

.SH "PROMPTS"

The -P option allows you to tailor the prompt to your preference.

The \-P option allows you to tailor the prompt to your preference.

The string given to the -P option replaces the specified prompt string.

The string given to the \-P option replaces the specified prompt string.

Certain characters in the string are interpreted specially.

The prompt mechanism is rather complicated to provide flexibility,

but the ordinary user need not understand the details of constructing

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an "m" means use the middle line,

a "b" means use the bottom line,

a "B" means use the line just after the bottom line,

and a "j" means use the "target" line, as specified by the -j option.

and a "j" means use the "target" line, as specified by the \-j option.

.IP "%B"

Replaced by the size of the current input file.

.IP "%c"

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See the discussion of the LESSEDIT feature below.

.IP "%f"

Replaced by the name of the current input file.

.IP "%F"

Replaced by the last component of the name of the current input file.

.IP "%i"

Replaced by the index of the current file in the list of

input files.

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Finally, any trailing spaces are truncated.

This is the default prompt.

For reference, here are the defaults for

the other two prompts (-m and -M respectively).

the other two prompts (\-m and \-M respectively).

Each is broken into two lines here for readability only.

.nf

.sp

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the examine command.

.IP "v"

the editing command

.IP "s -o"

.IP "s \-o"

log files

.IP "-k"

.IP "\-k"

use of lesskey files

.IP "-t"

.IP "\-t"

use of tags files

.IP " "

metacharacters in filenames, such as *

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.PP

Less can also be compiled to be permanently in "secure" mode.

.SH "COMPATIBILITY WITH MORE"

If the environment variable LESS_IS_MORE is set to 1,

or if the program is invoked via a file link named "more",

.I less

behaves (mostly) in conformance with the POSIX "more" command specification.

In this mode, less behaves differently in these ways:

.PP

The \-e option works differently.

If the \-e option is not set,

.I less

behaves as if the \-E option were set.

If the \-e option is set,

.I less

behaves as if the \-e and \-F options were set.

.PP

The \-m option works differently.

If the \-m option is not set, the medium prompt is used,

and it is prefixed with the string "--More--".

If the \-m option is set, the short prompt is used.

.PP

The \-n option acts like the \-z option.

The normal behavior of the \-n option is unavailable in this mode.

.PP

The parameter to the \-p option is taken to be a

.I less

command rather than a search pattern.

.PP

The LESS environment variable is ignored,

and the MORE environment variable is used in its place.

.SH "ENVIRONMENT VARIABLES"

Environment variables may be specified either in the system environment

as usual, or in a

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.I less

automatically.

.IP LESSANSIENDCHARS

Characters which are assumed to end an ANSI color escape sequence

Characters which may end an ANSI color escape sequence

(default "m").

.IP LESSANSIMIDCHARS

Characters which may appear between the ESC character and the

end character in an ANSI color escape sequence

(default "0123456789;[?!"'#%()*+\ ".

.IP LESSBINFMT

Format for displaying non-printable, non-control characters.

.IP LESSCHARDEF

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Editor prototype string (used for the v command).

See discussion under PROMPTS.

.IP LESSGLOBALTAGS

Name of the command used by the -t option to find global tags.

Name of the command used by the \-t option to find global tags.

Normally should be set to "global" if your system has the

.I global

(1) command. If not set, global tags are not used.

.IP LESSHISTFILE

Name of the history file used to remember search commands and

shell commands between invocations of

.I less.

If set to "\-" or "/dev/null", a history file is not used.

The default is "$HOME/.lesshst" on Unix systems, "$HOME/_lesshst" on

DOS and Windows systems, or "$HOME/lesshst.ini" or "$INIT/lesshst.ini"

on OS/2 systems.

.IP LESSHISTSIZE

The maximum number of commands to save in the history file.

The default is 100.

.IP LESSKEY

Name of the default lesskey(1) file.

.IP LESSKEY_SYSTEM

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See discussion under SECURITY.

.IP LESSSEPARATOR

String to be appended to a directory name in filename completion.

.IP LESSUTFBINFMT

Format for displaying non-printable Unicode code points.

.IP LESS_IS_MORE

Emulate the

.I more

(1) command.

.IP LINES

Sets the number of lines on the screen.

Takes precedence over the number of lines specified by the TERM variable.

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.SH "SEE ALSO"

lesskey(1)

.SH WARNINGS

The = command and prompts (unless changed by -P)

report the line numbers of the lines at the top and bottom of the screen,

but the byte and percent of the line after the one at the bottom of the screen.

.PP

If the :e command is used to name more than one file,

and one of the named files has been viewed previously,

the new files may be entered into the list in an unexpected order.

.PP

On certain older terminals (the so-called "magic cookie" terminals),

search highlighting will cause an erroneous display.

On such terminals, search highlighting is disabled by default

to avoid possible problems.

.PP

In certain cases, when search highlighting is enabled and

a search pattern begins with a ^,

more text than the matching string may be highlighted.

(This problem does not occur when less is compiled to use the POSIX

regular expression package.)

.PP

When viewing text containing ANSI color escape sequences using the -R option,

searching will not find text containing an embedded escape sequence.

Also, search highlighting may change the color of some of the text

which follows the highlighted text.

.PP

On some systems,

.I setlocale

claims that ASCII characters 0 thru 31 are control characters

rather than binary characters.

This causes

.I less

to treat some binary files as ordinary, non-binary files.

To workaround this problem, set the environment variable

LESSCHARSET to "ascii" (or whatever character set is appropriate).

.PP

See http://www.greenwoodsoftware.com/less for the latest list of known bugs in this

version of less.

.SH COPYRIGHT

.PP

less is part of the GNU project and is free software.

You can redistribute it and/or modify it

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.br

Send bug reports or comments to the above address or to bug-less@gnu.org.

.br

For more information, see the less homepage at http://www.greenwoodsoftware.com/less.

See http://www.greenwoodsoftware.com/less/bugs.html for the latest list of known bugs in less.

.br

For more information, see the less homepage at

.br

http://www.greenwoodsoftware.com/less.