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   more.1p    ( 1 )

постраничная основа (by-page basis)

Расширенное описание (Extended description)

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.1‐2017, 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.1‐2017, 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.