1MORE(1P)                   POSIX Programmer's Manual                  MORE(1P)
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PROLOG

6       This  manual  page is part of the POSIX Programmer's Manual.  The Linux
7       implementation of this interface may differ (consult the  corresponding
8       Linux  manual page for details of Linux behavior), or the interface may
9       not be implemented on Linux.
10
11

NAME

13       more — display files on a page-by-page basis
14

SYNOPSIS

16       more [−ceisu] [−n number] [−p command] [−t tagstring] [file...]
17

DESCRIPTION

19       The more utility shall read files and either write them to the terminal
20       on  a page-by-page basis or filter them to standard output. If standard
21       output is not a terminal device, all input files  shall  be  copied  to
22       standard  output  in  their  entirety,  without modification, except as
23       specified for the −s option. If standard output is a  terminal  device,
24       the  files shall be written a number of lines (one screenful) at a time
25       under the control of user commands. See the EXTENDED  DESCRIPTION  sec‐
26       tion.
27
28       Certain block-mode terminals do not have all the capabilities necessary
29       to support the complete more definition; they are incapable of  accept‐
30       ing commands that are not terminated with a <newline>.  Implementations
31       that support such terminals shall provide an operating mode to more  in
32       which  all  commands can be terminated with a <newline> on those termi‐
33       nals. This mode:
34
35        *  Shall be documented in the system documentation
36
37        *  Shall, at invocation, inform the user of  the  terminal  deficiency
38           that  requires  the <newline> usage and provide instructions on how
39           this warning can be suppressed in future invocations
40
41        *  Shall not be required for  implementations  supporting  only  fully
42           capable terminals
43
44        *  Shall not affect commands already requiring <newline> characters
45
46        *  Shall  not affect users on the capable terminals from using more as
47           described in this volume of POSIX.1‐2008
48

OPTIONS

50       The more utility shall  conform  to  the  Base  Definitions  volume  of
51       POSIX.1‐2008,  Section 12.2, Utility Syntax Guidelines, except that '+'
52       may be recognized as an option delimiter as well as '−'.
53
54       The following options shall be supported:
55
56       −c        If a screen is to be written that has no lines in common with
57                 the current screen, or more is writing its first screen, more
58                 shall not scroll the screen, but instead  shall  redraw  each
59                 line of the screen in turn, from the top of the screen to the
60                 bottom. In addition, if more is writing its first screen, the
61                 screen  shall be cleared. This option may be silently ignored
62                 on devices with insufficient terminal capabilities.
63
64       −e        Exit immediately after writing the last line of the last file
65                 in the argument list; see the EXTENDED DESCRIPTION section.
66
67       −i        Perform  pattern matching in searches without regard to case;
68                 see the Base Definitions volume of POSIX.1‐2008, Section 9.2,
69                 Regular Expression General Requirements.
70
71       −n number Specify  the  number of lines per screenful. The number argu‐
72                 ment is a positive decimal integer. The −n option shall over‐
73                 ride any values obtained from any other source.
74
75       −p command
76                 Each  time  a  screen  from a new file is displayed or redis‐
77                 played (including as a result of more commands; for  example,
78                 :p),  execute the more command(s) in the command arguments in
79                 the order specified, as if entered  by  the  user  after  the
80                 first  screen  has  been  displayed.  No intermediate results
81                 shall be displayed (that is, if the command is a movement  to
82                 a  screen  different  from  the normal first screen, only the
83                 screen resulting from the command shall be displayed.) If any
84                 of the commands fail for any reason, an informational message
85                 to this effect shall be  written,  and  no  further  commands
86                 specified  using  the  −p  option  shall be executed for this
87                 file.
88
89       −s        Behave as if consecutive empty  lines  were  a  single  empty
90                 line.
91
92       −t tagstring
93                 Write  the  screenful of the file containing the tag named by
94                 the tagstring argument. See the ctags utility. The tags  fea‐
95                 ture  represented  by  −t  tagstring  and  the  :t command is
96                 optional. It shall be provided on any system that  also  pro‐
97                 vides  a  conforming  implementation of ctags; otherwise, the
98                 use of −t produces undefined results.
99
100                 The filename resulting from the −t option shall be  logically
101                 added  as  a  prefix to the list of command line files, as if
102                 specified by the user. If the  tag  named  by  the  tagstring
103                 argument  is  not found, it shall be an error, and more shall
104                 take no further action.
105
106                 If the tag specifies a line number, the  first  line  of  the
107                 display  shall contain the beginning of that line. If the tag
108                 specifies a pattern, the first line of the display shall con‐
109                 tain  the  beginning of the matching text from the first line
110                 of the file that contains that pattern. If the line does  not
111                 exist  in the file or matching text is not found, an informa‐
112                 tional message to this effect shall be  displayed,  and  more
113                 shall display the default screen as if −t had not been speci‐
114                 fied.
115
116                 If both the −t tagstring and −p command  options  are  given,
117                 the  −t tagstring shall be processed first; that is, the file
118                 and starting line for the display shall be  as  specified  by
119                 −t,  and  then  the −p more command shall be executed. If the
120                 line (matching text) specified by the  −t  command  does  not
121                 exist  (is  not  found), no −p more command shall be executed
122                 for this file at any time.
123
124       −u        Treat a <backspace> as a printable  control  character,  dis‐
125                 played  as  an implementation-defined character sequence (see
126                 the EXTENDED DESCRIPTION  section),  suppressing  backspacing
127                 and the special handling that produces underlined or standout
128                 mode text on some terminal types.   Also,  do  not  ignore  a
129                 <carriage-return> at the end of a line.
130

OPERANDS

132       The following operand shall be supported:
133
134       file      A  pathname  of an input file. If no file operands are speci‐
135                 fied, the standard input shall be used. If a file is '−', the
136                 standard input shall be read at that point in the sequence.
137

STDIN

139       The  standard  input  shall be used only if no file operands are speci‐
140       fied, or if a file operand is '−'.
141

INPUT FILES

143       The input files being examined shall be text files. If standard  output
144       is  a  terminal, standard error shall be used to read commands from the
145       user. If standard output is a terminal, standard error is not readable,
146       and  command  input is needed, more may attempt to obtain user commands
147       from the controlling terminal (for example, /dev/tty); otherwise,  more
148       shall  terminate  with  an  error indicating that it was unable to read
149       user commands. If standard output is not a  terminal,  no  error  shall
150       result if standard error cannot be opened for reading.
151

ENVIRONMENT VARIABLES

153       The following environment variables shall affect the execution of more:
154
155       COLUMNS   Override  the  system-selected  horizontal display line size.
156                 See the Base Definitions volume of POSIX.1‐2008,  Chapter  8,
157                 Environment Variables for valid values and results when it is
158                 unset or null.
159
160       EDITOR    Used by the v command to select an editor. See  the  EXTENDED
161                 DESCRIPTION section.
162
163       LANG      Provide  a  default  value for the internationalization vari‐
164                 ables that are unset or null. (See the Base Definitions  vol‐
165                 ume  of POSIX.1‐2008, Section 8.2, Internationalization Vari‐
166                 ables for the precedence  of  internationalization  variables
167                 used to determine the values of locale categories.)
168
169       LC_ALL    If  set  to  a non-empty string value, override the values of
170                 all the other internationalization variables.
171
172       LC_COLLATE
173                 Determine the locale for the behavior of ranges,  equivalence
174                 classes,  and multi-character collating elements within regu‐
175                 lar expressions.
176
177       LC_CTYPE  Determine the locale for the interpretation of  sequences  of
178                 bytes of text data as characters (for example, single-byte as
179                 opposed to  multi-byte  characters  in  arguments  and  input
180                 files)  and  the behavior of character classes within regular
181                 expressions.
182
183       LC_MESSAGES
184                 Determine the locale that should be used to affect the format
185                 and contents of diagnostic messages written to standard error
186                 and informative messages written to standard output.
187
188       NLSPATH   Determine the location of message catalogs for the processing
189                 of LC_MESSAGES.
190
191       LINES     Override  the  system-selected  vertical screen size, used as
192                 the number of lines in a screenful. See the Base  Definitions
193                 volume  of POSIX.1‐2008, Chapter 8, Environment Variables for
194                 valid values and results when it is unset  or  null.  The  −n
195                 option  shall  take  precedence  over  the LINES variable for
196                 determining the number of lines in a screenful.
197
198       MORE      Determine  a  string  containing  options  described  in  the
199                 OPTIONS   section   preceded  with  <hyphen>  characters  and
200                 <blank>-separated as on the command line.  Any  command  line
201                 options  shall be processed after those in the MORE variable,
202                 as if the command line were:
203
204                     more $MORE options operands
205
206                 The MORE variable shall take precedence  over  the  TERM  and
207                 LINES  variables  for  determining  the  number of lines in a
208                 screenful.
209
210       TERM      Determine the name of the terminal type. If this variable  is
211                 unset or null, an unspecified default terminal type is used.
212

ASYNCHRONOUS EVENTS

214       Default.
215

STDOUT

217       The  standard  output  shall be used to write the contents of the input
218       files.
219

STDERR

221       The standard error shall be used for diagnostic messages and user  com‐
222       mands  (see the INPUT FILES section), and, if standard output is a ter‐
223       minal device, to write a prompting string. The prompting  string  shall
224       appear  on the screen line below the last line of the file displayed in
225       the current screenful. The prompt shall contain the name  of  the  file
226       currently  being  examined  and shall contain an end-of-file indication
227       and the name of the next file, if any, when prompting  at  the  end-of-
228       file. If an error or informational message is displayed, it is unspeci‐
229       fied whether it is contained in the prompt. If it is not  contained  in
230       the  prompt,  it shall be displayed and then the user shall be prompted
231       for a continuation character, at which point  another  message  or  the
232       user  prompt  may be displayed. The prompt is otherwise unspecified. It
233       is unspecified whether informational messages  are  written  for  other
234       user commands.
235

OUTPUT FILES

237       None.
238

EXTENDED DESCRIPTION

240       The  following section describes the behavior of more when the standard
241       output is a terminal device. If the standard output is not  a  terminal
242       device,  no  options other than −s shall have any effect, and all input
243       files shall be copied to standard output otherwise unmodified, at which
244       time more shall exit without further action.
245
246       The  number of lines available per screen shall be determined by the −n
247       option, if present, or by examining values in the environment (see  the
248       ENVIRONMENT  VARIABLES  section). If neither method yields a number, an
249       unspecified number of lines shall be used.
250
251       The maximum number of lines written shall be one less than this number,
252       because  the  screen  line after the last line written shall be used to
253       write a user prompt and user input. If  the  number  of  lines  in  the
254       screen  is  less than two, the results are undefined. It is unspecified
255       whether user input is permitted to be longer than the remainder of  the
256       single line where the prompt has been written.
257
258       The number of columns available per line shall be determined by examin‐
259       ing values in the environment (see the ENVIRONMENT VARIABLES  section),
260       with  a  default  value  as described in the Base Definitions volume of
261       POSIX.1‐2008, Chapter 8, Environment Variables.
262
263       Lines that are longer than the display shall be folded; the  length  at
264       which  folding occurs is unspecified, but should be appropriate for the
265       output device. Folding may occur between glyphs  of  single  characters
266       that take up multiple display columns.
267
268       When  standard output is a terminal and −u is not specified, more shall
269       treat <backspace> and <carriage-return> characters specially:
270
271        *  A character, followed first by a sequence of n <backspace>  charac‐
272           ters  (where  n  is the same as the number of column positions that
273           the character occupies), then by n <underscore>  characters  ('_'),
274           shall cause that character to be written as underlined text, if the
275           terminal type supports that. The n  <underscore>  characters,  fol‐
276           lowed  first by n <backspace> characters, then any character with n
277           column positions, shall also cause that character to be written  as
278           underlined text, if the terminal type supports that.
279
280        *  A  sequence of n <backspace> characters (where n is the same as the
281           number of column positions that the  previous  character  occupies)
282           that appears between two identical printable characters shall cause
283           the first of those two characters to be written as emboldened  text
284           (that is, visually brighter, standout mode, or inverse-video mode),
285           if the terminal type supports that, and the second to be discarded.
286           Immediately  subsequent  occurrences of <backspace>/character pairs
287           for that same character shall also be discarded. (For example,  the
288           sequence "a\ba\ba\ba" is interpreted as a single emboldened 'a'.)
289
290        *  The  more  utility  shall  logically  discard all other <backspace>
291           characters from the line as well as the  character  which  precedes
292           them, if any.
293
294        *  A  <carriage-return>  at the end of a line shall be ignored, rather
295           than being written as a non-printable character,  as  described  in
296           the next paragraph.
297
298       It  is  implementation-defined  how  other non-printable characters are
299       written. Implementations should use the same format that they  use  for
300       the ex print command; see the OPTIONS section within the ed utility. It
301       is unspecified whether a multi-column character shall be  separated  if
302       it  crosses  a  display  line  boundary; it shall not be discarded. The
303       behavior is unspecified if the number of columns on the display is less
304       than  the number of columns any single character in the line being dis‐
305       played would occupy.
306
307       When each new file is displayed (or redisplayed), more shall write  the
308       first  screen  of  the  file. Once the initial screen has been written,
309       more shall prompt for a user command. If the execution of the user com‐
310       mand  results  in  a  screen  that has lines in common with the current
311       screen, and the device has sufficient terminal capabilities, more shall
312       scroll  the  screen; otherwise, it is unspecified whether the screen is
313       scrolled or redrawn.
314
315       For all files but the last (including standard input  if  no  file  was
316       specified,  and  for  the  last  file as well, if the −e option was not
317       specified), when more has written the last line in the file, more shall
318       prompt  for  a  user command. This prompt shall contain the name of the
319       next file as well as an indication that more has  reached  end-of-file.
320       If  the user command is f, <control>‐F, <space>, j, <newline>, d, <con‐
321       trol>‐D, or s, more shall display the next file. Otherwise, if display‐
322       ing  the  last file, more shall exit. Otherwise, more shall execute the
323       user command specified.
324
325       Several of the commands described in this section  display  a  previous
326       screen from the input stream. In the case that text is being taken from
327       a non-rewindable stream, such as a pipe, it  is  implementation-defined
328       how much backwards motion is supported. If a command cannot be executed
329       because of a limitation on backwards motion, an error message  to  this
330       effect shall be displayed, the current screen shall not change, and the
331       user shall be prompted for another command.
332
333       If a command cannot be performed because there are  insufficient  lines
334       to  display, more shall alert the terminal. If a command cannot be per‐
335       formed because there are insufficient lines to display or a  /  command
336       fails:  if the input is the standard input, the last screen in the file
337       may be displayed; otherwise, the current  file  and  screen  shall  not
338       change, and the user shall be prompted for another command.
339
340       The  interactive commands in the following sections shall be supported.
341       Some commands can be preceded by a decimal integer, called count in the
342       following  descriptions. If not specified with the command, count shall
343       default to 1. In the following descriptions, pattern is a basic regular
344       expression,   as   described   in   the   Base  Definitions  volume  of
345       POSIX.1‐2008, Section 9.3, Basic Regular Expressions.  The term ``exam‐
346       ine''  is  historical  usage meaning ``open the file for viewing''; for
347       example, more foo would be expressed as examining file foo.
348
349       In the following descriptions, unless otherwise specified,  line  is  a
350       line in the more display, not a line from the file being examined.
351
352       In  the  following  descriptions,  the  current  position refers to two
353       things:
354
355        1. The position of the current line on the screen
356
357        2. The line number (in the file) of the current line on the screen
358
359       Usually, the line on the screen corresponding to the  current  position
360       is  the  third  line  on the screen. If this is not possible (there are
361       fewer than three lines to display or this is  the  first  page  of  the
362       file, or it is the last page of the file), then the current position is
363       either the first or last line on the screen as described later.
364
365   Help
366       Synopsis:
367                     h
368
369       Write a summary of these commands and other implementation-defined com‐
370       mands.  The behavior shall be as if the more utility were executed with
371       the −e option on a file that contained  the  summary  information.  The
372       user  shall  be prompted as described earlier in this section when end-
373       of-file is reached. If the user command is one of  those  specified  to
374       continue  to  the  next  file, more shall return to the file and screen
375       state from which the h command was executed.
376
377   Scroll Forward One Screenful
378       Synopsis:
379                     [count]f
380                     [count]<control>-F
381
382       Scroll forward count lines, with a default of one screenful.  If  count
383       is  more  than the screen size, only the final screenful shall be writ‐
384       ten.
385
386   Scroll Backward One Screenful
387       Synopsis:
388                     [count]b
389                     [count]<control>-B
390
391       Scroll backward count lines, with a default of one screenful  (see  the
392       −n  option).  If  count  is  more  than the screen size, only the final
393       screenful shall be written.
394
395   Scroll Forward One Line
396       Synopsis:
397                     [count]<space>
398                     [count]j
399                     [count]<newline>
400
401       Scroll forward count lines. The default count for the <space> shall  be
402       one  screenful;  for  j and <newline>, one line. The entire count lines
403       shall be written, even if count is more than the screen size.
404
405   Scroll Backward One Line
406       Synopsis:
407                     [count]k
408
409       Scroll backward count lines. The entire count lines shall  be  written,
410       even if count is more than the screen size.
411
412   Scroll Forward One Half Screenful
413       Synopsis:
414                     [count]d
415                     [count]<control>-D
416
417       Scroll  forward  count  lines, with a default of one half of the screen
418       size. If count is specified, it shall become the new default for subse‐
419       quent d, <control>‐D, and u commands.
420
421   Skip Forward One Line
422       Synopsis:
423                     [count]s
424
425       Display  the  screenful  beginning  with the line count lines after the
426       last line on the current screen. If count would cause the current posi‐
427       tion to be such that less than one screenful would be written, the last
428       screenful in the file shall be written.
429
430   Scroll Backward One Half Screenful
431       Synopsis:
432                     [count]u
433                     [count]<control>-U
434
435       Scroll backward count lines, with a default of one half of  the  screen
436       size. If count is specified, it shall become the new default for subse‐
437       quent d, <control>−D, u, and <control>−U  commands.  The  entire  count
438       lines shall be written, even if count is more than the screen size.
439
440   Go to Beginning of File
441       Synopsis:
442                     [count]g
443
444       Display the screenful beginning with line count.
445
446   Go to End-of-File
447       Synopsis:
448                     [count]G
449
450       If  count  is  specified, display the screenful beginning with the line
451       count.  Otherwise, display the last screenful of the file.
452
453   Refresh the Screen
454       Synopsis:
455                     r
456                     <control>-L
457
458       Refresh the screen.
459
460   Discard and Refresh
461       Synopsis:
462                     R
463
464       Refresh the screen, discarding any buffered input. If the current  file
465       is  non-seekable,  buffered input shall not be discarded and the R com‐
466       mand shall be equivalent to the r command.
467
468   Mark Position
469       Synopsis:
470                     mletter
471
472       Mark the current position with the letter named by letter, where letter
473       represents  the  name  of  one of the lowercase letters of the portable
474       character set. When a new file is examined, all marks may be lost.
475
476   Return to Mark
477       Synopsis:
478                     'letter
479
480       Return to the position that was previously marked with the letter named
481       by letter, making that line the current position.
482
483   Return to Previous Position
484       Synopsis:
485                     ''
486
487       Return  to  the position from which the last large movement command was
488       executed (where a ``large movement'' is defined as any movement of more
489       than a screenful of lines). If no such movements have been made, return
490       to the beginning of the file.
491
492   Search Forward for Pattern
493       Synopsis:
494                     [count]/[!]pattern<newline>
495
496       Display the screenful beginning with the countth  line  containing  the
497       pattern.  The  search  shall  start after the first line currently dis‐
498       played. The null regular expression ('/' followed by a <newline>) shall
499       repeat the search using the previous regular expression, with a default
500       count.  If the character '!'  is included, the matching lines shall  be
501       those  that  do  not contain the pattern.  If no match is found for the
502       pattern, a message to that effect shall be displayed.
503
504   Search Backward for Pattern
505       Synopsis:
506                     [count]?[!]pattern<newline>
507
508       Display the screenful beginning with the countth previous line contain‐
509       ing  the  pattern.  The  search shall start on the last line before the
510       first line currently displayed. The null regular expression ('?'   fol‐
511       lowed  by a <newline>) shall repeat the search using the previous regu‐
512       lar expression, with  a  default  count.   If  the  character  '!'   is
513       included,  matching  lines  shall be those that do not contain the pat‐
514       tern.  If no match is found for the pattern, a message to  that  effect
515       shall be displayed.
516
517   Repeat Search
518       Synopsis:
519                     [count]n
520
521       Repeat the previous search for countth line containing the last pattern
522       (or not containing the last pattern, if the previous search was "/!" or
523       "?!").
524
525   Repeat Search in Reverse
526       Synopsis:
527                     [count]N
528
529       Repeat  the search in the opposite direction of the previous search for
530       the countth line containing the last pattern  (or  not  containing  the
531       last pattern, if the previous search was "/!" or "?!").
532
533   Examine New File
534       Synopsis:
535                     :e [filename]<newline>
536
537       Examine a new file. If the filename argument is not specified, the cur‐
538       rent file (see the :n and :p commands below) shall be re-examined.  The
539       filename  shall  be  subjected  to the process of shell word expansions
540       (see Section 2.6, Word Expansions); if  more  than  a  single  pathname
541       results,  the  effects are unspecified.  If filename is a <number-sign>
542       ('#'), the previously examined file shall be re-examined.  If  filename
543       is  not  accessible for any reason (including that it is a non-seekable
544       file), an error message to this effect shall be displayed and the  cur‐
545       rent file and screen shall not change.
546
547   Examine Next File
548       Synopsis:
549                     [count]:n
550
551       Examine the next file. If a number count is specified, the countth next
552       file shall be examined. If filename refers to a non-seekable file,  the
553       results are unspecified.
554
555   Examine Previous File
556       Synopsis:
557                     [count]:p
558
559       Examine  the previous file. If a number count is specified, the countth
560       previous file shall be examined. If filename refers to  a  non-seekable
561       file, the results are unspecified.
562
563   Go to Tag
564       Synopsis:
565                     :t tagstring<newline>
566
567       If  the  file containing the tag named by the tagstring argument is not
568       the current file, examine the file, as if the :e command  was  executed
569       with  that file as the argument. Otherwise, or in addition, display the
570       screenful beginning with the tag, as described for the −t  option  (see
571       the OPTIONS section). If the ctags utility is not supported by the sys‐
572       tem, the use of :t produces undefined results.
573
574   Invoke Editor
575       Synopsis:
576                     v
577
578       Invoke an editor to edit the current file being examined.  If  standard
579       input  is  being examined, the results are unspecified. The name of the
580       editor shall be taken from the environment variable  EDITOR,  or  shall
581       default  to  vi.  If the last pathname component in EDITOR is either vi
582       or ex, the editor shall be invoked with a −c  linenumber  command  line
583       argument, where linenumber is the line number of the file line contain‐
584       ing the display line currently displayed  as  the  first  line  of  the
585       screen.  It  is implementation-defined whether line-setting options are
586       passed to editors other than vi and ex.
587
588       When the editor exits, more shall resume with the same file and  screen
589       as when the editor was invoked.
590
591   Display Position
592       Synopsis:
593                     =
594                     <control>-G
595
596       Write  a message for which the information references the first byte of
597       the line after the last line of the file on the  screen.  This  message
598       shall include the name of the file currently being examined, its number
599       relative to the total number of files there are to  examine,  the  line
600       number  in  the  file, the byte number and the total bytes in the file,
601       and what percentage of the file precedes the current position. If  more
602       is  reading  from  standard input, or the file is shorter than a single
603       screen, the line number, the byte number, the total bytes, and the per‐
604       centage need not be written.
605
606   Quit
607       Synopsis:
608                     q
609                     :q
610                     ZZ
611
612       Exit more.
613

EXIT STATUS

615       The following exit values shall be returned:
616
617        0    Successful completion.
618
619       >0    An error occurred.
620

CONSEQUENCES OF ERRORS

622       If  an error is encountered accessing a file when using the :n command,
623       more shall attempt to examine the next file in the argument  list,  but
624       the  final  exit  status  shall be affected. If an error is encountered
625       accessing a file via the :p command, more shall attempt to examine  the
626       previous  file in the argument list, but the final exit status shall be
627       affected. If an error is encountered accessing a file via the  :e  com‐
628       mand,  more  shall remain in the current file and the final exit status
629       shall not be affected.
630
631       The following sections are informative.
632

APPLICATION USAGE

634       When the standard output is not a terminal, only the −s  filter-modifi‐
635       cation  option  is effective. This is based on historical practice. For
636       example, a typical implementation of man pipes its output through  more
637       −s  to squeeze excess white space for terminal users. When man is piped
638       to lp, however, it is undesirable for this squeezing to happen.
639

EXAMPLES

641       The −p allows arbitrary commands to be executed at the  start  of  each
642       file.  Examples are:
643
644       more −p G file1 file2
645             Examine each file starting with its last screenful.
646
647       more −p 100 file1 file2
648             Examine  each file starting with line 100 in the current position
649             (usually the third line, so line 98 would be the first line writ‐
650             ten).
651
652       more −p /100 file1 file2
653             Examine  each  file  starting  with the first line containing the
654             string "100" in the current position
655

RATIONALE

657       The more utility, available in BSD and BSD-derived systems, was  chosen
658       as  the  prototype  for the POSIX file display program since it is more
659       widely available than either the public-domain program less or than pg,
660       a  pager  provided  in  System V. The 4.4 BSD more is the model for the
661       features selected; it is almost fully upwards-compatible from  the  4.3
662       BSD version in wide use and has become more amenable for vi users. Sev‐
663       eral features originally derived from various file  editors,  found  in
664       both  less  and  pg,  have been added to this volume of POSIX.1‐2008 as
665       they have proved extremely popular with users.
666
667       There are inconsistencies between more and vi that result from histori‐
668       cal  practice.  For example, the single-character commands h, f, b, and
669       <space> are screen movers in more, but  cursor  movers  in  vi.   These
670       inconsistencies  were  maintained  because the cursor movements are not
671       applicable to more and the powerful functionality achieved without  the
672       use of the control key justifies the differences.
673
674       The  tags  interface  has been included in a program that is not a text
675       editor because it promotes another degree of consistent operation  with
676       vi.   It  is  conceivable  that the paging environment of more would be
677       superior for browsing source code files in some circumstances.
678
679       The operating mode referred to  for  block-mode  terminals  effectively
680       adds a <newline> to each Synopsis line that currently has none. So, for
681       example, d<newline> would page one screenful. The mode could  be  trig‐
682       gered  by  a  command  line option, environment variable, or some other
683       method. The details are not imposed  by  this  volume  of  POSIX.1‐2008
684       because  there are so few systems known to support such terminals. Nev‐
685       ertheless, it was considered that all systems should be able to support
686       more  given  the  exception cited for this small community of terminals
687       because, in comparison to vi, the cursor movements are few and the com‐
688       mand set relatively amenable to the optional <newline> characters.
689
690       Some versions of more provide a shell escaping mechanism similar to the
691       ex !  command. The standard developers did not consider that  this  was
692       necessary  in  a  paginator,  particularly given the wide acceptance of
693       multiple window terminals and job  control  features.  (They  chose  to
694       retain  such features in the editors and mailx because the shell inter‐
695       action also gives an opportunity to modify the editing buffer, which is
696       not applicable to more.)
697
698       The  −p (position) option replaces the + command because of the Utility
699       Syntax Guidelines. The  +command  option  is  no  longer  specified  by
700       POSIX.1‐2008  but may be present in some implementations. In early pro‐
701       posals, it took a pattern argument, but historical  less  provided  the
702       more general facility of a command. It would have been desirable to use
703       the same −c as ex and vi, but the letter was already in use.
704
705       The text stating ``from a non-rewindable stream ... implementations may
706       limit  the amount of backwards motion supported'' would allow an imple‐
707       mentation that permitted no backwards motion beyond text already on the
708       screen.  It  was  not possible to require a minimum amount of backwards
709       motion that would be effective for all conceivable  device  types.  The
710       implementation  should  allow  the  user to back up as far as possible,
711       within device and reasonable memory allocation constraints.
712
713       Historically, non-printable characters were displayed  using  the  ARPA
714       standard mappings, which are as follows:
715
716        1. Printable characters are left alone.
717
718        2. Control  characters  less  than \177 are represented as followed by
719           the character offset from the '@' character in the ASCII  map;  for
720           example, \007 is represented as 'G'.
721
722        3. \177 is represented as followed by '?'.
723
724       The  display  of  characters having their eighth bit set was less stan‐
725       dard. Existing implementations use hex  (0x00),  octal  (\000),  and  a
726       meta-bit  display.  (The  latter displayed characters with their eighth
727       bit set as the two characters "M−", followed by the  seven-bit  display
728       as  described  previously.)  The  latter probably has the best claim to
729       historical practice because it was used with the −v option of 4 BSD and
730       4 BSD-derived versions of the cat utility since 1980.
731
732       No specific display format is required by POSIX.1‐2008. Implementations
733       are encouraged to conform to historic practice in the  absence  of  any
734       strong reason to diverge.
735

FUTURE DIRECTIONS

737       None.
738

SEE ALSO

740       Chapter 2, Shell Command Language, ctags, ed, ex, vi
741
742       The  Base  Definitions  volume  of POSIX.1‐2008, Chapter 8, Environment
743       Variables, Section 9.2, Regular Expression General  Requirements,  Sec‐
744       tion  9.3,  Basic  Regular  Expressions,  Section  12.2, Utility Syntax
745       Guidelines
746
748       Portions of this text are reprinted and reproduced in  electronic  form
749       from IEEE Std 1003.1, 2013 Edition, Standard for Information Technology
750       -- Portable Operating System Interface (POSIX),  The  Open  Group  Base
751       Specifications Issue 7, Copyright (C) 2013 by the Institute of Electri‐
752       cal and Electronics Engineers,  Inc  and  The  Open  Group.   (This  is
753       POSIX.1-2008  with  the  2013  Technical Corrigendum 1 applied.) In the
754       event of any discrepancy between this version and the original IEEE and
755       The  Open Group Standard, the original IEEE and The Open Group Standard
756       is the referee document. The original Standard can be  obtained  online
757       at http://www.unix.org/online.html .
758
759       Any  typographical  or  formatting  errors that appear in this page are
760       most likely to have been introduced during the conversion of the source
761       files  to  man page format. To report such errors, see https://www.ker
762       nel.org/doc/man-pages/reporting_bugs.html .
763
764
765
766IEEE/The Open Group                  2013                             MORE(1P)
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