Annotation of src/usr.bin/less/less.1, Revision 1.54
1.54 ! naddy 1: .\" $OpenBSD: less.1,v 1.53 2019/05/07 23:05:12 schwarze Exp $
1.1 millert 2: .\"
1.32 shadchin 3: .\" Copyright (C) 1984-2012 Mark Nudelman
1.1 millert 4: .\"
1.5 millert 5: .\" Redistribution and use in source and binary forms, with or without
6: .\" modification, are permitted provided that the following conditions
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1.7 jmc 11: .\" notice in the documentation and/or other materials provided with
1.5 millert 12: .\" the distribution.
1.1 millert 13: .\"
1.5 millert 14: .\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY
15: .\" EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
1.7 jmc 16: .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
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1.54 ! naddy 26: .Dd $Mdocdate: May 7 2019 $
1.1 millert 27: .Dt LESS 1
28: .Os
29: .Sh NAME
1.34 jmc 30: .Nm less
1.11 jmc 31: .Nd view files
1.1 millert 32: .Sh SYNOPSIS
1.34 jmc 33: .Nm less
1.53 schwarze 34: .Op Fl ?~AaBCcdEeFfGgIiJKLMmNnQqRrSsUuVWwX
1.34 jmc 35: .Op Fl b Ar n
36: .Op Fl h Ar n
37: .Op Fl j Ar n
1.1 millert 38: .Op Fl k Ar keyfile
1.12 jmc 39: .Op Fl O | o Ar logfile
40: .Op Fl P Ar prompt
1.1 millert 41: .Op Fl p Ar pattern
1.12 jmc 42: .Op Fl T Ar tagsfile
1.1 millert 43: .Op Fl t Ar tag
1.45 jmc 44: .Op Fl x Ar n , Ns Ar ...
1.34 jmc 45: .Op Fl y Ar n
1.44 bentley 46: .Op Fl z Ar n
1.53 schwarze 47: .Op Fl # Ar n
1.34 jmc 48: .Op Ar
1.1 millert 49: .Sh DESCRIPTION
50: .Nm
51: is a program similar to the traditional
52: .Xr more 1 ,
1.37 jmc 53: but with many more features.
54: It displays text one screenful at a time.
55: After showing each screenful, it prompts the user for a command.
56: When showing the last line of a file,
57: .Nm
58: displays a prompt indicating end of file and the name of the next file
59: to examine, if any.
60: It then waits for input from the user.
1.1 millert 61: .Pp
1.38 jmc 62: Commands are based on both traditional
63: .Xr more 1
64: and
65: .Xr vi 1 .
66: Commands may be preceded by a decimal number,
1.44 bentley 67: called
68: .Ar N
69: in the descriptions below.
1.38 jmc 70: The number is used by some commands, as indicated.
71: .Pp
1.1 millert 72: This version of
73: .Nm
74: also acts as
75: .Xr more 1
76: if it is called as
1.37 jmc 77: .Nm more ,
78: or if the
79: .Ev LESS_IS_MORE
80: environment variable is set.
81: The main differences between the two are summarized in the
82: .Sx COMPATIBILITY WITH MORE
83: section, below.
84: .Pp
1.1 millert 85: A long option name may be abbreviated as long as the abbreviation is
86: unambiguous.
87: Such option names need only have their first letter capitalized;
88: the remainder of the name may be in either case.
1.44 bentley 89: For example,
90: .Fl -Quit-at-eof
91: is equivalent to
92: .Fl -QUIT-AT-EOF .
1.1 millert 93: .Pp
1.36 jmc 94: The options are as follows:
1.1 millert 95: .Bl -tag -width XXXX
1.6 jmc 96: .It Fl \&? | -help
1.1 millert 97: This option displays a summary of the commands accepted by
98: .Nm
1.44 bentley 99: (the same as the
100: .Ic h
101: command).
1.1 millert 102: (Depending on how your shell interprets the question mark,
1.44 bentley 103: it may be necessary to quote the question mark, thus:
104: .Ql Fl Ns \e? . )
1.23 shadchin 105: .It Fl A | -SEARCH-SKIP-SCREEN
106: Causes all forward searches (not just non-repeated searches)
107: to start just after the target line, and all backward searches
108: to start just before the target line.
109: Thus, forward searches will skip part of the displayed screen
110: (from the first line up to and including the target line).
111: Similarly backwards searches will skip the displayed screen
112: from the last line up to and including the target line.
1.44 bentley 113: This was the default behavior in
114: .Nm
115: versions prior to 441.
1.1 millert 116: .It Fl a | -search-skip-screen
1.23 shadchin 117: By default, forward searches start at the top of the displayed screen
118: and backwards searches start at the bottom of the displayed screen
1.44 bentley 119: (except for repeated searches invoked by the
120: .Ic n
121: or
122: .Ic N
123: commands,
124: which start after or before the
125: .Dq target
126: line respectively; see the
127: .Fl j
128: option for more about the target line).
129: The
130: .Fl a
131: option causes forward searches to instead start at the bottom of the screen
1.23 shadchin 132: and backward searches to start at the top of the screen,
1.1 millert 133: thus skipping all lines displayed on the screen.
1.12 jmc 134: .It Fl B | -auto-buffers
135: By default, when data is read from a pipe,
136: buffers are allocated automatically as needed.
137: If a large amount of data is read from the pipe, this can cause
138: a large amount of memory to be allocated.
1.44 bentley 139: The
140: .Fl B
141: option disables this automatic allocation of buffers for pipes,
142: so that only 64K (or the amount of space specified by the
143: .Fl b
144: option) is used for the pipe.
145: .Sy Warning :
146: use of
147: .Fl B
148: can result in erroneous display, since only the
1.23 shadchin 149: most recently viewed part of the piped data is kept in memory;
1.12 jmc 150: any earlier data is lost.
1.44 bentley 151: .It Fl b Ar n | Fl -buffers Ns = Ns Ar n
1.1 millert 152: Specifies the amount of buffer space
153: .Nm
154: will use for each file, in units of kilobytes (1024 bytes).
155: By default 64K of buffer space is used for each file
1.44 bentley 156: (unless the file is a pipe; see the
157: .Fl B
158: option).
159: The
160: .Fl b
161: option specifies instead that
162: .Ar n
163: kilobytes of buffer space should be used for each file.
164: If
165: .Ar n
166: is -1, buffer space is unlimited; that is,
1.23 shadchin 167: the entire file can be read into memory.
1.12 jmc 168: .It Fl C | -CLEAR-SCREEN
1.44 bentley 169: Same as
170: .Fl c ,
171: for compatibility with older versions of
172: .Nm .
1.1 millert 173: .It Fl c | -clear-screen
1.27 jmc 174: Causes full screen repaints to be painted from the bottom of the screen.
175: By default, full screen repaints are done from the top line down
176: to avoid the position of the display being moved
1.26 nicm 177: when using interactive commands.
1.33 millert 178: .It Fl d | -dumb
1.44 bentley 179: The
180: .Fl d
181: option suppresses the error message normally displayed if the terminal is dumb;
182: that is, if the terminal lacks some important capability,
1.1 millert 183: such as the ability to clear the screen or scroll backward.
1.44 bentley 184: The
185: .Fl d
186: option does not otherwise change the behavior of
1.1 millert 187: .Nm
188: on a dumb terminal.
1.12 jmc 189: .It Fl E | -QUIT-AT-EOF
190: Causes
191: .Nm
192: to automatically exit the first time it reaches end-of-file.
1.1 millert 193: .It Fl e | -quit-at-eof
194: Causes
195: .Nm
196: to automatically exit the second time it reaches end-of-file.
197: By default, the only way to exit
198: .Nm
1.44 bentley 199: is via the
200: .Ic q
201: command.
1.12 jmc 202: .It Fl F | -quit-if-one-screen
1.1 millert 203: Causes
204: .Nm
1.12 jmc 205: to automatically exit if the entire file can be displayed on the first screen.
1.1 millert 206: .It Fl f | -force
207: Forces non-regular files to be opened.
208: (A non-regular file is a directory or a device special file.)
209: Also suppresses the warning message when a binary file is opened.
210: By default,
211: .Nm
212: will refuse to open non-regular files.
1.12 jmc 213: .It Fl G | -HILITE-SEARCH
1.44 bentley 214: The
215: .Fl G
216: option suppresses all highlighting of strings found by search commands.
1.1 millert 217: .It Fl g | -hilite-search
218: Normally,
219: .Nm
1.44 bentley 220: will highlight all strings which match the last search command.
221: The
222: .Fl g
223: option changes this behavior to highlight only the particular string
1.1 millert 224: which was found by the last search command.
225: This can cause
226: .Nm
227: to run somewhat faster than the default.
1.44 bentley 228: .It Fl h Ar n | Fl -max-back-scroll Ns = Ns Ar n
1.1 millert 229: Specifies a maximum number of lines to scroll backward.
230: If it is necessary to scroll backward more than n lines,
231: the screen is repainted in a forward direction instead.
1.44 bentley 232: (If the terminal does not have the ability to scroll backward,
233: .Sq Fl h Ns 0
234: is implied.)
1.12 jmc 235: .It Fl I | -IGNORE-CASE
1.44 bentley 236: Like
237: .Fl i ,
238: but searches ignore case even if the pattern contains uppercase
1.12 jmc 239: letters.
1.1 millert 240: .It Fl i | -ignore-case
241: Causes searches to ignore case; that is,
242: uppercase and lowercase are considered identical.
243: This option is ignored if any uppercase letters appear in the search pattern;
244: in other words,
245: if a pattern contains uppercase letters, then that search does not ignore case.
1.12 jmc 246: .It Fl J | -status-column
247: Displays a status column at the left edge of the screen.
248: The status column shows the lines that matched the current search.
1.44 bentley 249: The status column is also used if the
250: .Fl w
251: or
252: .Fl W
253: option is in effect.
254: .It Fl j Ar n | Fl -jump-target Ns = Ns Ar n
255: Specifies a line on the screen where the
256: .Dq target
257: line is to be positioned.
1.23 shadchin 258: The target line is the line specified by any command to
259: search for a pattern, jump to a line number,
260: jump to a file percentage or jump to a tag.
261: The screen line may be specified by a number: the top line on the screen
1.1 millert 262: is 1, the next is 2, and so on.
263: The number may be negative to specify a line relative to the bottom
264: of the screen: the bottom line on the screen is -1, the second
265: to the bottom is -2, and so on.
1.23 shadchin 266: Alternately, the screen line may be specified as a fraction of the height
267: of the screen, starting with a decimal point: .5 is in the middle of the
268: screen, .3 is three tenths down from the first line, and so on.
269: If the line is specified as a fraction, the actual line number
270: is recalculated if the terminal window is resized, so that the
271: target line remains at the specified fraction of the screen height.
1.44 bentley 272: If any form of the
273: .Fl j
274: option is used,
1.23 shadchin 275: forward searches begin at the line immediately after the target line,
276: and backward searches begin at the target line,
1.44 bentley 277: unless changed by
278: .Fl a
279: or
280: .Fl A .
281: For example, if
282: .Sq Fl j Ns 4
283: is used, the target line is the fourth line on the screen,
284: so forward searches begin at the fifth line on the screen.
1.23 shadchin 285: .It Fl K | -quit-on-intr
286: Causes
287: .Nm
1.44 bentley 288: to exit immediately (with status 2) when an interrupt character (usually
289: .Ic ^C )
290: is typed.
1.23 shadchin 291: Normally, an interrupt character causes
292: .Nm
293: to stop whatever it is doing and return to its command prompt.
1.24 jmc 294: Note that use of this option makes it impossible to return to the
1.44 bentley 295: command prompt from the
296: .Ic F
297: command.
298: .It Fl k Ar keyfile | Fl -lesskey-file Ns = Ns Ar keyfile
1.1 millert 299: Causes
300: .Nm
301: to open and interpret the named file as a
302: .Xr lesskey 1
303: file.
1.44 bentley 304: Multiple
305: .Fl k
306: options may be specified.
1.36 jmc 307: If the
308: .Ev LESSKEY
309: or
310: .Ev LESSKEY_SYSTEM
311: environment variable is set, or if a lesskey file is found in a standard place
312: (see
313: .Sx KEY BINDINGS ) ,
314: it is also used as a lesskey file.
315: .It Fl L | -no-lessopen
316: Ignore the
317: .Ev LESSOPEN
318: environment variable (see the
319: .Sx INPUT PREPROCESSOR
320: section below).
321: This option can be set from within
322: .Nm less ,
323: but it will apply only to files opened subsequently, not to the
324: file which is currently open.
325: .It Fl M | -LONG-PROMPT
326: Causes
327: .Nm
328: to prompt even more verbosely than
1.39 jmc 329: .Xr more 1 .
1.36 jmc 330: .It Fl m | -long-prompt
331: Causes
332: .Nm
1.39 jmc 333: to prompt verbosely, like
334: .Xr more 1 ,
335: with the percent into the file.
1.36 jmc 336: By default,
337: .Nm
338: prompts with a colon.
339: .It Fl N | -LINE-NUMBERS
340: Causes a line number to be displayed at the beginning of each line in the
341: display.
342: .It Fl n | -line-numbers
343: Suppresses line numbers.
344: The default (to use line numbers) may cause
345: .Nm
346: to run more slowly in some cases, especially with a very large input file.
1.44 bentley 347: Suppressing line numbers with the
348: .Fl n
349: option will avoid this problem.
1.36 jmc 350: Using line numbers means: the line number will be displayed in the verbose
1.44 bentley 351: prompt and in the
352: .Ic =
353: command, and the
354: .Ic v
355: command will pass the current line
356: number to the editor (see also the discussion of
357: .Ev LESSEDIT
358: in
1.36 jmc 359: .Sx PROMPTS
360: below).
1.44 bentley 361: .It Fl O Ar logfile | Fl -LOG-FILE Ns = Ns Ar logfile
362: The
363: .Fl O
364: option is like
365: .Fl o ,
366: but it will overwrite an existing file without asking for confirmation.
1.36 jmc 367: .Pp
368: If no log file has been specified,
1.44 bentley 369: the
370: .Fl o
371: and
372: .Fl O
373: options can be used from within
1.36 jmc 374: .Nm
375: to specify a log file.
376: Without a file name, they will simply report the name of the log file.
1.44 bentley 377: The
378: .Ic s
379: command is equivalent to specifying
380: .Fl o
381: from within
382: .Nm .
383: .It Fl o Ar logfile | Fl -log-file Ns = Ns Ar logfile
1.36 jmc 384: Causes
385: .Nm
386: to copy its input to the named file as it is being viewed.
387: This applies only when the input file is a pipe, not an ordinary file.
388: If the file already exists,
389: .Nm
390: will ask for confirmation before overwriting it.
1.44 bentley 391: .It Fl P Ar prompt | Fl -prompt Ns = Ns Ar prompt
1.36 jmc 392: Provides a way to tailor the three prompt styles to your own preference.
393: This option would normally be put in the
394: .Ev LESS
395: environment variable, rather than being typed in with each
396: .Nm
397: command.
398: Such an option must either be the last option in the
399: .Ev LESS
400: variable, or be terminated by a dollar sign.
1.44 bentley 401: .Bl -item
402: .It
403: .Fl Ps Ar string
404: changes the default (short) prompt to
405: .Ar string .
406: .It
407: .Fl Pm
408: changes the medium
409: .Pq Fl m
410: prompt.
411: .It
412: .Fl PM
413: changes the long
414: .Pq Fl M
415: prompt.
416: .It
417: .Fl Ph
418: changes the prompt for the help screen.
419: .It
420: .Fl P=
421: changes the message printed by the
422: .Ic =
423: command.
424: .It
425: .Fl Pw
426: changes the message printed while waiting for data (in the
427: .Ic F
428: command).
429: .El
1.36 jmc 430: All prompt strings consist of a sequence of letters and special escape
431: sequences.
432: See the section on
433: .Sx PROMPTS
434: for more details.
1.44 bentley 435: .It Fl p Ar pattern | Fl -pattern Ns = Ns Ar pattern
436: The
437: .Fl p
438: option on the command line is equivalent to specifying
439: .Cm +/ Ns Ar pattern ;
1.36 jmc 440: that is, it tells
441: .Nm
442: to start at the first occurrence of pattern in the file.
443: .It Fl Q | -QUIET | -SILENT
1.44 bentley 444: Causes totally quiet operation: the terminal bell is never rung.
1.36 jmc 445: .It Fl q | -quiet | -silent
1.44 bentley 446: Causes moderately quiet operation:
1.36 jmc 447: the terminal bell is not rung if an attempt is made to scroll past the end
448: of the file or before the beginning of the file.
1.44 bentley 449: If the terminal has a visual bell, it is used instead.
1.36 jmc 450: The bell will be rung on certain other errors,
451: such as typing an invalid character.
452: The default is to ring the terminal bell in all such cases.
453: .It Fl R | -RAW-CONTROL-CHARS
1.44 bentley 454: Like
455: .Fl r ,
456: but only ANSI color escape sequences are output in raw form.
457: Unlike
458: .Fl r ,
459: the screen appearance is maintained correctly in most cases.
460: ANSI color escape sequences are sequences of the form:
1.36 jmc 461: .Pp
462: .Dl ESC \&[ ... m
463: .Pp
1.44 bentley 464: where the
465: .Dq ...
466: is zero or more color specification characters.
1.36 jmc 467: For the purpose of keeping track of screen appearance,
468: ANSI color escape sequences are assumed to not move the cursor.
469: You can make
470: .Nm
1.44 bentley 471: think that characters other than
472: .Sq m
473: can end ANSI color escape sequences by setting the environment variable
1.36 jmc 474: .Ev LESSANSIENDCHARS
475: to the list of characters which can end a color escape sequence.
476: And you can make
477: .Nm
478: think that characters other than the standard ones may appear between
1.44 bentley 479: the
480: .Cm ESC
481: and the
482: .Cm m
483: by setting the environment variable
1.36 jmc 484: .Ev LESSANSIMIDCHARS
485: to the list of characters which can appear.
486: .It Fl r | -raw-control-chars
1.44 bentley 487: Causes raw control characters to be displayed.
1.36 jmc 488: The default is to display control characters using the caret notation;
1.44 bentley 489: for example, a control-A (octal 001) is displayed as
490: .Sq ^A .
491: .Sy Warning :
492: when the
493: .Fl r
494: option is used,
1.36 jmc 495: .Nm
496: cannot keep track of the actual appearance of the screen
497: (since this depends on how the screen responds to
498: each type of control character).
499: Thus, various display problems may result,
500: such as long lines being split in the wrong place.
501: .It Fl S | -chop-long-lines
502: Causes lines longer than the screen width to be
503: chopped (truncated) rather than wrapped.
504: That is, the portion of a long line that does not fit in
505: the screen width is not shown.
506: The default is to wrap long lines; that is, display the remainder
507: on the next line.
508: .It Fl s | -squeeze-blank-lines
509: Causes consecutive blank lines to be squeezed into a single blank line.
1.44 bentley 510: .It Fl T Ar tagsfile | Fl -tag-file Ns = Ns Ar tagsfile
511: Specifies a tags file to be used instead of
512: .Pa tags .
1.36 jmc 513: .It Xo
514: .Fl t Ar tag |
515: .Fl -tag Ns = Ns Ar tag
516: .Xc
1.44 bentley 517: The
518: .Fl t
519: option, followed immediately by a
520: .Ar tag ,
1.36 jmc 521: will edit the file containing that tag.
522: For this to work, tag information must be available;
1.44 bentley 523: for example, there may be a file in the current directory called
524: .Pa tags ,
1.36 jmc 525: which was previously built by
526: .Xr ctags 1
527: or an equivalent command.
1.44 bentley 528: The
529: .Fl t
530: option may also be specified from within
1.36 jmc 531: .Nm
1.44 bentley 532: (using the
533: .Ic -
534: command) as a way of examining a new file.
535: The command
536: .Ic :t
537: is equivalent to specifying
538: .Fl t
539: from within
540: .Nm .
1.36 jmc 541: .It Fl U | -UNDERLINE-SPECIAL
542: Causes backspaces, tabs and carriage returns to be
543: treated as control characters;
1.44 bentley 544: that is, they are handled as specified by the
545: .Fl r
546: option.
1.36 jmc 547: .Pp
1.44 bentley 548: By default, if neither
549: .Fl u
550: nor
551: .Fl U
552: is given, backspaces which appear adjacent
1.36 jmc 553: to an underscore character are treated specially:
554: the underlined text is displayed
555: using the terminal's hardware underlining capability.
556: Also, backspaces which appear between two identical characters
557: are treated specially:
558: the overstruck text is printed
559: using the terminal's hardware boldface capability.
560: Other backspaces are deleted, along with the preceding character.
561: Carriage returns immediately followed by a newline are deleted.
1.44 bentley 562: Other carriage returns are handled as specified by the
563: .Fl r
564: option.
1.36 jmc 565: Text which is overstruck or underlined can be searched for
1.44 bentley 566: if neither
567: .Fl u
568: nor
569: .Fl U
570: is in effect.
1.36 jmc 571: .It Fl u | -underline-special
572: Causes backspaces and carriage returns to be treated as printable characters;
573: that is, they are sent to the terminal when they appear in the input.
574: .It Fl V | -version
575: Displays the version number of
1.44 bentley 576: .Nm .
1.36 jmc 577: .It Fl W | -HILITE-UNREAD
1.44 bentley 578: Like
579: .Fl w ,
580: but temporarily highlights the first new line after any
1.36 jmc 581: forward movement command larger than one line.
582: .It Fl w | -hilite-unread
1.44 bentley 583: Temporarily highlights the first new line after a forward movement
1.36 jmc 584: of a full page.
1.44 bentley 585: The first new line is the line immediately following the line previously
1.36 jmc 586: at the bottom of the screen.
1.44 bentley 587: Also highlights the target line after a
588: .Ic g
589: or
590: .Ic p
591: command.
1.36 jmc 592: The highlight is removed at the next command which causes movement.
1.44 bentley 593: The entire line is highlighted, unless the
594: .Fl J
595: option is in effect,
1.36 jmc 596: in which case only the status column is highlighted.
597: .It Fl X | -no-init
598: Disables sending the termcap initialization and deinitialization strings
599: to the terminal.
600: This is sometimes desirable if the deinitialization string does
601: something unnecessary, like clearing the screen.
602: .It Xo
1.44 bentley 603: .Fl x Ar n , Ns Ar ... |
604: .Fl -tabs Ns = Ns Ar n , Ns Ar ...
1.36 jmc 605: .Xc
606: Sets tab stops.
1.44 bentley 607: If only one
608: .Ar n
609: is specified, tab stops are set at multiples of
610: .Ar n .
1.36 jmc 611: If multiple values separated by commas are specified, tab stops are set at
612: those positions, and then continue with the same spacing as the last two.
1.44 bentley 613: For example,
614: .Sq Fl x Ns 9,17
615: will set tabs at positions 9, 17, 25, 33, etc.
616: The default for
617: .Ar n
618: is 8.
619: .It Fl y Ar n | Fl -max-forw-scroll Ns = Ns Ar n
1.36 jmc 620: Specifies a maximum number of lines to scroll forward.
621: If it is necessary to scroll forward more than n lines,
622: the screen is repainted instead.
1.44 bentley 623: The
624: .Fl c
625: or
626: .Fl C
627: option may be used to repaint from the top of the screen if desired.
1.36 jmc 628: By default, any forward movement causes scrolling.
1.44 bentley 629: .It Fl z Ar n | Fl -window Ns = Ns Ar n
630: Changes the default scrolling window size to
631: .Ar n
632: lines.
1.36 jmc 633: The default is one screenful.
1.44 bentley 634: The
635: .Ic z
636: and
637: .Ic w
638: commands can also be used to change the window size.
639: The
640: .Cm z
641: may be omitted for compatibility with some versions of
1.39 jmc 642: .Xr more 1 .
1.36 jmc 643: If the number
644: .Ar n
645: is negative, it indicates
646: .Ar n
647: lines less than the current screen size.
1.44 bentley 648: For example, if the screen is 24 lines,
649: .Fl z Ns -4
650: sets the scrolling window to 20 lines.
1.36 jmc 651: If the screen is resized to 40 lines,
652: the scrolling window automatically changes to 36 lines.
653: .It Fl -follow-name
1.44 bentley 654: Normally, if the input file is renamed while an
655: .Ic F
656: command is executing,
1.1 millert 657: .Nm
1.36 jmc 658: will continue to display the contents of the original file despite
659: its name change.
1.44 bentley 660: If
661: .Fl -follow-name
662: is specified, during an
663: .Ic F
664: command
1.1 millert 665: .Nm
1.36 jmc 666: will periodically attempt to reopen the file by name.
667: If the reopen succeeds and the file is a different file from the original
668: (which means that a new file has been created
669: with the same name as the original (now renamed) file),
1.1 millert 670: .Nm
1.36 jmc 671: will display the contents of that new file.
672: .It Fl -no-keypad
673: Disables sending the keypad initialization and deinitialization strings
674: to the terminal.
675: This is sometimes useful if the keypad strings make the numeric
676: keypad behave in an undesirable manner.
677: .It Fl -use-backslash
678: This option changes the interpretations of options which follow this one.
1.44 bentley 679: After the
680: .Fl -use-backslash
681: option, any backslash in an option string is
1.36 jmc 682: removed and the following character is taken literally.
683: This allows a dollar sign to be included in option strings.
1.44 bentley 684: .It Fl \&" Ar cc | Fl -quotes Ns = Ns Ar cc
1.36 jmc 685: Changes the filename quoting character.
686: This may be necessary if you are trying to name a file
687: which contains both spaces and quote characters.
1.44 bentley 688: If
689: .Ar cc
690: is a single character, this changes the quote character to that character.
1.36 jmc 691: Filenames containing a space should then be surrounded by that character
692: rather than by double quotes.
1.44 bentley 693: If
694: .Ar cc
695: consists of two characters, this changes the open quote to the first character,
1.36 jmc 696: and the close quote to the second character.
697: Filenames containing a space should then be preceded by the open quote
698: character and followed by the close quote character.
699: Note that even after the quote characters are changed, this option
1.44 bentley 700: remains
701: .Fl \&"
702: (a dash followed by a double quote).
1.36 jmc 703: .It Fl ~ | -tilde
704: Normally lines after end of file are displayed as a single tilde (~).
705: This option causes lines after end of file to be displayed as blank lines.
1.53 schwarze 706: .It Fl # Ar n | Fl -shift Ns = Ns Ar n
707: Specifies the default number
708: .Ar n
709: of positions to scroll horizontally
1.36 jmc 710: in the RIGHTARROW and LEFTARROW commands.
1.53 schwarze 711: If
712: .Ar n
713: is zero, it sets the default number of
1.36 jmc 714: positions to one half of the screen width.
715: Alternately, the number may be specified as a fraction of the width
716: of the screen, starting with a decimal point: .5 is half of the
717: screen width, .3 is three tenths of the screen width, and so on.
718: If the number is specified as a fraction, the actual number of
719: scroll positions is recalculated if the terminal window is resized,
720: so that the actual scroll remains at the specified fraction
721: of the screen width.
722: .It Fl -
1.44 bentley 723: A command line argument of
724: .Fl -
725: marks the end of option arguments.
1.36 jmc 726: Any arguments following this are interpreted as filenames.
1.44 bentley 727: This can be useful when viewing a file whose name begins with a
728: .Sq -
729: or
730: .Sq + .
1.36 jmc 731: .It Cm +
732: If a command line option begins with +,
733: the remainder of that option is taken to be an initial command to
1.44 bentley 734: .Nm .
735: For example,
736: .Cm +G
737: tells
1.36 jmc 738: .Nm
739: to start at the end of the file rather than the beginning,
1.44 bentley 740: and
741: .Cm +/xyz
742: tells it to start at the first occurrence of
743: .Dq xyz
744: in the file.
745: As a special case,
746: .Cm + Ns Ar number
747: acts like
748: .Cm + Ns Ar number Ns g ;
1.36 jmc 749: that is, it starts the display at the specified line number
1.44 bentley 750: (however, see the caveat under the
751: .Ic g
752: command below).
753: If the option starts with
754: .Cm ++ ,
755: the initial command applies to every file being viewed, not just the first one.
756: The
757: .Cm +
758: command described previously
1.36 jmc 759: may also be used to set (or change) an initial command for every file.
760: .El
761: .Sh COMMANDS
762: In the following descriptions, ^X means control-X.
763: ESC stands for the ESCAPE key; for example ESC-v means the
764: two character sequence "ESCAPE", then "v".
765: .Bl -tag -width XXXX
766: .It Ic h | H
767: Help: display a summary of these commands.
768: If you forget all the other commands, remember this one.
769: .It Ic SPACE | ^V | f | ^F
1.44 bentley 770: Scroll forward N lines, default one window (see option
771: .Fl z
772: above).
1.36 jmc 773: If N is more than the screen size, only the final screenful is displayed.
774: Warning: some systems use ^V as a special literalization character.
775: .It Ic z
776: Like SPACE, but if N is specified, it becomes the new window size.
777: .It Ic ESC-SPACE
778: Like SPACE, but scrolls a full screenful, even if it reaches
779: end-of-file in the process.
780: .It Ic ENTER | RETURN | ^N | e | ^E | j | ^J
781: Scroll forward N lines, default 1.
782: The entire N lines are displayed, even if N is more than the screen size.
783: .It Ic d | ^D
784: Scroll forward N lines, default one half of the screen size.
785: If N is specified, it becomes the new default for subsequent d and u commands.
786: .It Ic b | ^B | ESC-v
1.44 bentley 787: Scroll backward N lines, default one window (see option
788: .Fl z
789: above).
1.36 jmc 790: If N is more than the screen size, only the final screenful is displayed.
791: .It Ic w
792: Like ESC-v, but if N is specified, it becomes the new window size.
793: .It Ic y | ^Y | ^P | k | ^K
794: Scroll backward N lines, default 1.
795: The entire N lines are displayed, even if N is more than the screen size.
796: Warning: some systems use ^Y as a special job control character.
797: .It Ic u | ^U
798: Scroll backward N lines, default one half of the screen size.
799: If N is specified, it becomes the new default for subsequent d and u commands.
800: .It Ic ESC-) | RIGHTARROW
801: Scroll horizontally right N characters, default half the screen width
1.44 bentley 802: (see the
803: .Fl #
804: option).
1.36 jmc 805: If a number N is specified, it becomes the default for future
806: RIGHTARROW and LEFTARROW commands.
1.44 bentley 807: While the text is scrolled, it acts as though the
808: .Fl S
809: option (chop lines) were in effect.
1.36 jmc 810: .It Ic ESC-( | LEFTARROW
811: Scroll horizontally left N
1.44 bentley 812: characters, default half the screen width (see the
813: .Fl #
814: option).
1.36 jmc 815: If a number N is specified, it becomes the default for future
816: RIGHTARROW and LEFTARROW commands.
817: .It Ic r | ^R | ^L
818: Repaint the screen.
819: .It Ic R
820: Repaint the screen, discarding any buffered input.
821: Useful if the file is changing while it is being viewed.
822: .It Ic F
823: Scroll forward, and keep trying to read when the end of file is reached.
824: Normally this command would be used when already at the end of the file.
825: It is a way to monitor the tail of a file which is growing
826: while it is being viewed.
827: (The behavior is similar to the "tail -f" command.)
828: .It Ic ESC-F
829: Like F, but as soon as a line is found which matches
830: the last search pattern, the terminal bell is rung
831: and forward scrolling stops.
832: .It Ic g | < | ESC-<
833: Go to line N in the file, default 1 (beginning of file).
834: (Warning: this may be slow if N is large.)
835: .It Ic G | > | ESC->
836: Go to line N in the file, default the end of the file.
837: (Warning: this may be slow if N is large,
838: or if N is not specified and standard input, rather than a file,
839: is being read.)
840: .It Ic p | %
841: Go to a position N percent into the file.
842: N should be between 0 and 100, and may contain a decimal point.
843: .It Ic P
844: Go to the line containing byte offset N in the file.
845: .It Ic {
846: If a left curly bracket appears in the top line displayed
847: on the screen, the { command will go to the matching right curly bracket.
848: The matching right curly bracket is positioned on the bottom
849: line of the screen.
850: If there is more than one left curly bracket on the top line, a number N
851: may be used to specify the N-th bracket on the line.
852: .It Ic }
853: If a right curly bracket appears in the bottom line displayed on the screen,
854: the } command will go to the matching left curly bracket.
855: The matching left curly bracket is positioned on the top
856: line of the screen.
857: If there is more than one right curly bracket on the top line,
858: a number N may be used to specify the N-th bracket on the line.
859: .It Ic \&(
860: Like {, but applies to parentheses rather than curly brackets.
861: .It Ic \&)
862: Like }, but applies to parentheses rather than curly brackets.
863: .It Ic \&[
864: Like {, but applies to square brackets rather than curly brackets.
865: .It Ic \&]
866: Like }, but applies to square brackets rather than curly brackets.
867: .It Ic ESC-^F
868: Followed by two characters, acts like {,
869: but uses the two characters as open and close brackets, respectively.
870: For example, "ESC ^F < >" could be used to
871: go forward to the > which matches the < in the top displayed line.
872: .It Ic ESC-^B
873: Followed by two characters, acts like },
874: but uses the two characters as open and close brackets, respectively.
875: For example, "ESC ^B < >" could be used to
876: go backward to the < which matches the > in the bottom displayed line.
877: .It Ic m
878: Followed by any lowercase letter, marks the current position with that letter.
879: .It Ic '
880: (Single quote.)
881: Followed by any lowercase letter, returns to the position which
882: was previously marked with that letter.
883: Followed by another single quote, returns to the position at
884: which the last "large" movement command was executed.
885: Followed by a ^ or $, jumps to the beginning or end of the file respectively.
886: Marks are preserved when a new file is examined,
887: so the ' command can be used to switch between input files.
888: .It Ic ^X^X
889: Same as single quote.
890: .It Ic /pattern
891: Search forward in the file for the N-th line containing the pattern.
892: N defaults to 1.
893: The pattern is a regular expression, as recognized by
894: the regular expression library supplied by your system.
895: The search starts at the first line displayed
1.44 bentley 896: (but see the
897: .Fl a
898: and
899: .Fl j
900: options, which change this).
1.1 millert 901: .Pp
1.36 jmc 902: Certain characters are special if entered at the beginning of the pattern;
903: they modify the type of search rather than become part of the pattern:
904: .Bl -tag -width Ds
905: .It Ic ^N | \&!
906: Search for lines which do NOT match the pattern.
907: .It Ic ^E | *
908: Search multiple files.
909: That is, if the search reaches the END of the current file
910: without finding a match,
911: the search continues in the next file in the command line list.
912: .It Ic ^F | @
913: Begin the search at the first line of the FIRST file
914: in the command line list,
915: regardless of what is currently displayed on the screen
1.44 bentley 916: or the settings of the
917: .Fl a
918: or
919: .Fl j
920: options.
1.36 jmc 921: .It Ic ^K
922: Highlight any text which matches the pattern on the current screen,
923: but don't move to the first match (KEEP current position).
924: .It Ic ^R
925: Don't interpret regular expression metacharacters;
926: that is, do a simple textual comparison.
927: .El
928: .It Ic ?pattern
929: Search backward in the file for the N-th line containing the pattern.
930: The search starts at the line immediately before the top line displayed.
1.1 millert 931: .Pp
1.36 jmc 932: Certain characters are special, as in the / command:
933: .Bl -tag -width Ds
934: .It Ic ^N | \&!
935: Search for lines which do NOT match the pattern.
936: .It Ic ^E | *
937: Search multiple files.
938: That is, if the search reaches the beginning of the current file
939: without finding a match,
940: the search continues in the previous file in the command line list.
941: .It Ic ^F | @
942: Begin the search at the last line of the last file
943: in the command line list,
944: regardless of what is currently displayed on the screen
1.44 bentley 945: or the settings of the
946: .Fl a
947: or
948: .Fl j
949: options.
1.36 jmc 950: .It Ic ^K
951: As in forward searches.
952: .It Ic ^R
953: As in forward searches.
954: .El
955: .It Ic ESC-/pattern
956: Same as "/*".
957: .It Ic ESC-?pattern
958: Same as "?*".
959: .It Ic n
960: Repeat previous search, for N-th line containing the last pattern.
961: If the previous search was modified by ^N, the search is made for the
962: N-th line NOT containing the pattern.
963: If the previous search was modified by ^E, the search continues
964: in the next (or previous) file if not satisfied in the current file.
965: If the previous search was modified by ^R, the search is done
966: without using regular expressions.
967: There is no effect if the previous search was modified by ^F or ^K.
968: .It Ic N
969: Repeat previous search, but in the reverse direction.
970: .It Ic ESC-n
971: Repeat previous search, but crossing file boundaries.
972: The effect is as if the previous search were modified by *.
973: .It Ic ESC-N
974: Repeat previous search, but in the reverse direction
975: and crossing file boundaries.
976: .It Ic ESC-u
977: Undo search highlighting.
978: Turn off highlighting of strings matching the current search pattern.
979: If highlighting is already off because of a previous ESC-u command,
980: turn highlighting back on.
981: Any search command will also turn highlighting back on.
1.44 bentley 982: (Highlighting can also be disabled by toggling the
983: .Fl G
984: option;
1.36 jmc 985: in that case search commands do not turn highlighting back on.)
986: .It Ic &pattern
987: Display only lines which match the pattern;
988: lines which do not match the pattern are not displayed.
989: If pattern is empty (if you type & immediately followed by ENTER),
990: any filtering is turned off, and all lines are displayed.
991: While filtering is in effect, an ampersand is displayed at the
992: beginning of the prompt,
993: as a reminder that some lines in the file may be hidden.
1.1 millert 994: .Pp
1.36 jmc 995: Certain characters are special as in the / command:
996: .Bl -tag -width Ds
997: .It Ic ^N | !
998: Display only lines which do NOT match the pattern.
999: .It Ic ^R
1000: Don't interpret regular expression metacharacters;
1001: that is, do a simple textual comparison.
1002: .El
1003: .It Ic :e Op Ar filename
1004: Examine a new file.
1005: If the filename is missing, the "current" file (see the :n and :p commands
1006: below) from the list of files in the command line is re-examined.
1007: A percent sign (%) in the filename is replaced by the name of the
1008: current file.
1009: A pound sign (#) is replaced by the name of the previously examined file.
1010: However, two consecutive percent signs are simply
1011: replaced with a single percent sign.
1012: This allows you to enter a filename that contains a percent sign
1013: in the name.
1014: Similarly, two consecutive pound signs are replaced with a single pound sign.
1015: The filename is inserted into the command line list of files
1016: so that it can be seen by subsequent :n and :p commands.
1017: If the filename consists of several files, they are all inserted into
1018: the list of files and the first one is examined.
1019: If the filename contains one or more spaces,
1020: the entire filename should be enclosed in double quotes
1.44 bentley 1021: (also see the
1022: .Fl \&"
1023: option).
1.36 jmc 1024: .It Ic ^X^V | E
1025: Same as :e.
1026: Warning: some systems use ^V as a special literalization character.
1027: On such systems, you may not be able to use ^V.
1028: .It Ic :n
1029: Examine the next file (from the list of files given in the command line).
1030: If a number N is specified, the N-th next file is examined.
1031: .It Ic :p
1032: Examine the previous file in the command line list.
1033: If a number N is specified, the N-th previous file is examined.
1034: .It Ic :t
1035: Go to the specified tag.
1036: .It Ic :x
1037: Examine the first file in the command line list.
1038: If a number N is specified, the N-th file in the list is examined.
1039: .It Ic :d
1040: Remove the current file from the list of files.
1041: .It Ic t
1042: Go to the next tag, if there were more than one matches for the current tag.
1.44 bentley 1043: See the
1044: .Fl t
1045: option for more details about tags.
1.36 jmc 1046: .It Ic T
1047: Go to the previous tag, if there were more than one matches for the current tag.
1048: .It Ic = | ^G | :f
1049: Prints some information about the file being viewed, including its name
1050: and the line number and byte offset of the bottom line being displayed.
1051: If possible, it also prints the length of the file,
1052: the number of lines in the file
1053: and the percent of the file above the last displayed line.
1054: .It Ic \-
1055: Followed by one of the command line option letters (see
1.44 bentley 1056: .Sx DESCRIPTION
1057: above),
1.36 jmc 1058: this will change the setting of that option
1059: and print a message describing the new setting.
1060: If a ^P (CONTROL-P) is entered immediately after the dash,
1061: the setting of the option is changed but no message is printed.
1.44 bentley 1062: If the option letter has a numeric value (such as
1063: .Fl b
1064: or
1065: .Fl h ) ,
1066: or a string value (such as
1067: .Fl P
1068: or
1069: .Fl t ) ,
1.36 jmc 1070: a new value may be entered after the option letter.
1071: If no new value is entered, a message describing
1072: the current setting is printed and nothing is changed.
1073: .It Ic \-\-
1074: Like the \- command, but takes a long option name (see
1.44 bentley 1075: .Sx DESCRIPTION
1076: above)
1.36 jmc 1077: rather than a single option letter.
1078: You must press ENTER or RETURN after typing the option name.
1079: A ^P immediately after the second dash suppresses printing of a
1080: message describing the new setting, as in the \- command.
1081: .It Ic \-+
1082: Followed by one of the command line option letters this will reset the
1083: option to its default setting and print a message describing the new setting.
1.44 bentley 1084: (The "\-+X" command does the same thing as
1085: .Sq Fl + Ns X
1086: on the command line.)
1.36 jmc 1087: This does not work for string-valued options.
1088: .It Ic \-\-+
1089: Like the \-+ command, but takes a long option name
1090: rather than a single option letter.
1091: .It Ic \-!
1092: Followed by one of the command line option letters, this will reset the
1093: option to the "opposite" of its default setting and print a message
1094: describing the new setting.
1095: This does not work for numeric or string-valued options.
1096: .It Ic \-\-!
1097: Like the \-! command, but takes a long option name
1098: rather than a single option letter.
1099: .It Ic _
1100: (Underscore.)
1101: Followed by one of the command line option letters,
1102: this will print a message describing the current setting of that option.
1103: The setting of the option is not changed.
1104: .It Ic __
1105: (Double underscore.)
1106: Like the _ (underscore) command, but takes a long option name
1107: rather than a single option letter.
1108: You must press ENTER or RETURN after typing the option name.
1109: .It Ic +cmd
1110: Causes the specified cmd to be executed each time a new file is examined.
1111: For example, +G causes
1.23 shadchin 1112: .Nm
1.36 jmc 1113: to initially display each file starting at the end rather than the beginning.
1114: .It Ic V
1115: Prints the version number of
1.12 jmc 1116: .Nm
1.36 jmc 1117: being run.
1118: .It Ic q | Q | :q | :Q | ZZ
1119: Exits
1.1 millert 1120: .Nm less .
1.36 jmc 1121: .El
1.1 millert 1122: .Pp
1.36 jmc 1123: The following
1124: four
1125: commands may or may not be valid, depending on your particular installation.
1126: .Bl -tag -width XXXX
1127: .It Ic v
1128: Invokes an editor to edit the current file being viewed.
1129: The editor is taken from the environment variable
1130: .Ev VISUAL ,
1131: if defined,
1132: or
1133: .Ev EDITOR
1134: if
1135: .Ev VISUAL
1136: is not defined,
1137: or defaults to "vi" if neither
1138: .Ev VISUAL
1139: nor
1140: .Ev EDITOR
1141: is defined.
1142: See also the discussion of LESSEDIT under the section on
1143: .Sx PROMPTS
1144: below.
1145: .It Ic | <m> Ar shell-command
1146: <m> represents any mark letter.
1147: Pipes a section of the input file to the given shell command.
1148: The section of the file to be piped is between the first line on
1149: the current screen and the position marked by the letter.
1150: <m> may also be ^ or $ to indicate beginning or end of file respectively.
1151: If <m> is . or newline, the current screen is piped.
1152: .It Ic s Ar filename
1153: Save the input to a file.
1154: This only works if the input is a pipe, not an ordinary file.
1.1 millert 1155: .El
1156: .Sh LINE EDITING
1157: When entering command line at the bottom of the screen
1158: (for example, a filename for the :e command,
1159: or the pattern for a search command),
1160: certain keys can be used to manipulate the command line.
1161: Most commands have an alternate form in [ brackets ] which can be used if
1162: a key does not exist on a particular keyboard.
1163: Any of these special keys may be entered literally by preceding
1164: it with the "literal" character, either ^V or ^A.
1165: A backslash itself may also be entered literally by entering two backslashes.
1166: .Bl -tag -width Ds
1167: .It LEFTARROW [ ESC-h ]
1168: Move the cursor one space to the left.
1169: .It RIGHTARROW [ ESC-l ]
1170: Move the cursor one space to the right.
1171: .It ^LEFTARROW [ ESC-b or ESC-LEFTARROW ]
1172: (That is, CONTROL and LEFTARROW simultaneously.)
1173: Move the cursor one word to the left.
1174: .It ^RIGHTARROW [ ESC-w or ESC-RIGHTARROW ]
1175: (That is, CONTROL and RIGHTARROW simultaneously.)
1176: Move the cursor one word to the right.
1177: .It HOME [ ESC-0 ]
1178: Move the cursor to the beginning of the line.
1179: .It END [ ESC-$ ]
1180: Move the cursor to the end of the line.
1181: .It BACKSPACE
1182: Delete the character to the left of the cursor,
1183: or cancel the command if the command line is empty.
1184: .It DELETE or [ ESC-x ]
1185: Delete the character under the cursor.
1186: .It ^BACKSPACE [ ESC-BACKSPACE ]
1187: (That is, CONTROL and BACKSPACE simultaneously.)
1188: Delete the word to the left of the cursor.
1189: .It ^DELETE [ ESC-X or ESC-DELETE ]
1190: (That is, CONTROL and DELETE simultaneously.)
1191: Delete the word under the cursor.
1192: .It UPARROW [ ESC-k ]
1193: Retrieve the previous command line.
1.32 shadchin 1194: If you first enter some text and then press UPARROW,
1195: it will retrieve the previous command which begins with that text.
1.1 millert 1196: .It DOWNARROW [ ESC-j ]
1197: Retrieve the next command line.
1.32 shadchin 1198: If you first enter some text and then press DOWNARROW,
1199: it will retrieve the next command which begins with that text.
1.1 millert 1200: .It TAB
1201: Complete the partial filename to the left of the cursor.
1202: If it matches more than one filename, the first match
1203: is entered into the command line.
1204: Repeated TABs will cycle through the other matching filenames.
1205: If the completed filename is a directory, a "/" is appended to the filename.
1206: The environment variable
1207: .Ev LESSSEPARATOR
1208: can be used to specify a different character to append to a directory name.
1209: .It BACKTAB [ ESC-TAB ]
1210: Like TAB, but cycles in the reverse direction through the matching filenames.
1211: .It ^L
1212: Complete the partial filename to the left of the cursor.
1213: If it matches more than one filename, all matches are entered into
1214: the command line (if they fit).
1215: .It ^U
1216: Delete the entire command line,
1217: or cancel the command if the command line is empty.
1218: If you have changed your line-kill character to something
1219: other than ^U, that character is used instead of ^U.
1.23 shadchin 1220: .It "^G"
1221: Delete the entire command line and return to the main prompt.
1.1 millert 1222: .El
1223: .Sh KEY BINDINGS
1224: You may define your own
1225: .Nm
1226: commands by using the program
1227: .Xr lesskey 1
1228: to create a lesskey file.
1229: This file specifies a set of command keys and an action
1230: associated with each key.
1231: You may also use lesskey
1232: to change the line-editing keys (see
1233: .Sx LINE EDITING ) ,
1234: and to set environment variables.
1235: If the environment variable
1236: .Ev LESSKEY
1237: is set,
1238: .Nm
1239: uses that as the name of the lesskey file.
1240: Otherwise,
1241: .Nm
1242: looks for a lesskey file called "$HOME/.less".
1243: See the
1244: .Xr lesskey 1
1245: manual page for more details.
1246: .Pp
1247: A system-wide lesskey file may also be set up to provide key bindings.
1248: If a key is defined in both a local lesskey file and in the
1249: system-wide file, key bindings in the local file take precedence over
1250: those in the system-wide file.
1251: If the environment variable
1252: .Ev LESSKEY_SYSTEM
1253: is set,
1254: .Nm
1255: uses that as the name of the system-wide lesskey file.
1256: Otherwise,
1257: .Nm
1258: looks in a standard place for the system-wide lesskey file:
1259: On
1260: .Ox ,
1261: the system-wide lesskey file is
1262: .Pa /etc/sysless .
1263: .Sh INPUT PREPROCESSOR
1264: You may define an "input preprocessor" for
1265: .Nm less .
1266: Before
1267: .Nm less
1268: opens a file, it first gives your input preprocessor a chance to modify the
1269: way the contents of the file are displayed.
1270: An input preprocessor is simply an executable program (or shell script),
1271: which writes the contents of the file to a different file,
1272: called the replacement file.
1273: The contents of the replacement file are then displayed
1274: in place of the contents of the original file.
1275: However, it will appear to the user as if the original file is opened;
1276: that is,
1277: .Nm less
1278: will display the original filename as the name of the current file.
1279: .Pp
1280: An input preprocessor receives one command line argument, the original filename,
1281: as entered by the user.
1282: It should create the replacement file, and when finished
1283: print the name of the replacement file to its standard output.
1284: If the input preprocessor does not output a replacement filename,
1285: .Nm
1286: uses the original file, as normal.
1287: The input preprocessor is not called when viewing standard input.
1288: To set up an input preprocessor, set the
1289: .Ev LESSOPEN
1290: environment variable to a command line which will invoke your
1291: input preprocessor.
1292: This command line should include one occurrence of the string "%s",
1293: which will be replaced by the filename
1294: when the input preprocessor command is invoked.
1295: .Pp
1296: When
1297: .Nm
1298: closes a file opened in such a way, it will call another program,
1299: called the input postprocessor,
1300: which may perform any desired clean-up action (such as deleting the
1301: replacement file created by
1302: .Ev LESSOPEN ) .
1303: This program receives two command line arguments, the original filename
1304: as entered by the user, and the name of the replacement file.
1305: To set up an input postprocessor, set the
1306: .Ev LESSCLOSE
1307: environment variable to a command line which will invoke your
1308: input postprocessor.
1309: It may include two occurrences of the string "%s";
1310: the first is replaced with the original name of the file and the second
1311: with the name of the replacement file, which was output by
1312: .Ev LESSOPEN .
1313: .Pp
1314: For example, these two scripts will allow you
1315: to keep files in compressed format, but still let
1316: .Nm
1317: view them directly:
1318: .Pp
1319: lessopen.sh:
1320: .Bd -literal -offset indent
1321: #! /bin/sh
1322: case "$1" in
1323: *.Z) uncompress -c $1 >/tmp/less.$$ 2>/dev/null
1324: if [ -s /tmp/less.$$ ]; then
1325: echo /tmp/less.$$
1326: else
1327: rm -f /tmp/less.$$
1328: fi
1329: ;;
1330: esac
1331: .Ed
1332: .Pp
1333: lessclose.sh:
1334: .Bd -literal -offset indent
1335: #! /bin/sh
1336: rm $2
1337: .Ed
1338: .Pp
1339: To use these scripts, put them both where they can be executed and
1340: set LESSOPEN="lessopen.sh\ %s", and LESSCLOSE="lessclose.sh\ %s\ %s".
1341: More complex LESSOPEN and LESSCLOSE scripts may be written
1342: to accept other types of compressed files, and so on.
1343: .Pp
1344: It is also possible to set up an input preprocessor to
1345: pipe the file data directly to
1346: .Nm less ,
1347: rather than putting the data into a replacement file.
1348: This avoids the need to decompress the entire file before starting to view it.
1349: An input preprocessor that works this way is called an input pipe.
1350: An input pipe, instead of writing the name of a replacement file on
1351: its standard output,
1352: writes the entire contents of the replacement file on its standard output.
1353: If the input pipe does not write any characters on its standard output,
1354: then there is no replacement file and
1355: .Nm
1356: uses the original file, as normal.
1357: To use an input pipe, make the first character in the
1358: .Ev LESSOPEN
1359: environment variable a vertical bar (|) to signify that the
1360: input preprocessor is an input pipe.
1361: .Pp
1362: For example, this script will work like the previous example scripts:
1363: .Pp
1364: lesspipe.sh:
1365: .Bd -literal -offset indent
1366: #! /bin/sh
1367: case "$1" in
1368: *.Z) uncompress -c $1 2>/dev/null
1.32 shadchin 1369: *) exit 1
1.1 millert 1370: ;;
1371: esac
1.32 shadchin 1372: exit $?
1.1 millert 1373: .Ed
1374: .Pp
1375: To use this script, put it where it can be executed and set
1376: LESSOPEN="|lesspipe.sh %s".
1.32 shadchin 1377: .Pp
1378: Note that a preprocessor cannot output an empty file, since that
1379: is interpreted as meaning there is no replacement, and
1380: the original file is used.
1381: To avoid this, if
1382: .Ev LESSOPEN
1383: starts with two vertical bars,
1384: the exit status of the script becomes meaningful.
1385: If the exit status is zero, the output is considered to be
1386: replacement text, even if it empty.
1387: If the exit status is nonzero, any output is ignored and the
1388: original file is used.
1389: For compatibility with previous versions of
1390: .Nm less ,
1391: if
1392: .Ev LESSOPEN
1393: starts with only one vertical bar, the exit status
1394: of the preprocessor is ignored.
1395: .Pp
1.1 millert 1396: When an input pipe is used, a LESSCLOSE postprocessor can be used,
1397: but it is usually not necessary since there is no replacement file to clean up.
1398: In this case, the replacement file name passed to the LESSCLOSE
1399: postprocessor is "-".
1.23 shadchin 1400: .Pp
1401: For compatibility with previous versions of
1402: .Nm less ,
1403: the input preprocessor or pipe is not used if
1404: .Nm
1405: is viewing standard input.
1406: However, if the first character of LESSOPEN is a dash (-),
1407: the input preprocessor is used on standard input as well as other files.
1408: In this case, the dash is not considered to be part of
1409: the preprocessor command.
1410: If standard input is being viewed, the input preprocessor is passed
1411: a file name consisting of a single dash.
1412: Similarly, if the first two characters of LESSOPEN are vertical bar and dash
1.32 shadchin 1413: (|-) or two vertical bars and a dash (||-),
1414: the input pipe is used on standard input as well as other files.
1.23 shadchin 1415: Again, in this case the dash is not considered to be part of
1416: the input pipe command.
1.1 millert 1417: .Sh NATIONAL CHARACTER SETS
1418: There are three types of characters in the input file:
1419: .Bl -tag -width "control characters"
1420: .It normal characters
1421: Can be displayed directly to the screen.
1422: .It control characters
1423: Should not be displayed directly, but are expected to be found
1424: in ordinary text files (such as backspace and tab).
1425: .It binary characters
1426: Should not be displayed directly and are not expected to be found
1427: in text files.
1428: .El
1429: .Pp
1430: A "character set" is simply a description of which characters are to
1431: be considered normal, control, and binary.
1432: .Nm
1.51 tb 1433: will determine the character set to use from the environment (see
1434: .Xr locale 1 ) .
1.1 millert 1435: .Pp
1436: Control and binary characters are displayed in standout (reverse video).
1437: Each such character is displayed in caret notation if possible
1438: (e.g. ^A for control-A).
1439: Caret notation is used only if inverting the 0100 bit results in a
1440: normal printable character.
1441: Otherwise, the character is displayed as a hex number in angle brackets.
1442: This format can be changed by setting the
1443: .Ev LESSBINFMT
1444: environment variable.
1445: LESSBINFMT may begin with a "*" and one character to select
1446: the display attribute:
1447: "*k" is blinking, "*d" is bold, "*u" is underlined, "*s" is standout,
1448: and "*n" is normal.
1449: If LESSBINFMT does not begin with a "*", normal attribute is assumed.
1450: The remainder of LESSBINFMT is a string which may include one
1451: printf-style escape sequence (a % followed by x, X, o, d, etc.).
1452: For example, if LESSBINFMT is "*u[%x]", binary characters
1453: are displayed in underlined hexadecimal surrounded by brackets.
1.23 shadchin 1454: The default if no LESSBINFMT is specified is "*s<%02X>".
1455: Warning: the result of expanding the character via LESSBINFMT must
1456: be less than 31 characters.
1457: .Pp
1458: When the character set is utf-8, the
1459: .Ev LESSUTFBINFMT
1460: environment variable
1461: acts similarly to LESSBINFMT but it applies to Unicode code points
1462: that were successfully decoded but are unsuitable for display (e.g.,
1463: unassigned code points).
1464: Its default value is "<U+%04lX>".
1465: Note that LESSUTFBINFMT and LESSBINFMT share their display attribute
1466: setting ("*x") so specifying one will affect both;
1467: LESSUTFBINFMT is read after LESSBINFMT so its setting, if any,
1468: will have priority.
1469: Problematic octets in a UTF-8 file (octets of a truncated sequence,
1470: octets of a complete but non-shortest form sequence, illegal octets,
1471: and stray trailing octets)
1472: are displayed individually using LESSBINFMT so as to facilitate diagnostic
1473: of how the UTF-8 file is ill-formed.
1.1 millert 1474: .Sh PROMPTS
1.44 bentley 1475: The
1476: .Fl P
1477: option allows you to tailor the prompt to your preference.
1478: The string given to the
1479: .Fl P
1480: option replaces the specified prompt string.
1.1 millert 1481: Certain characters in the string are interpreted specially.
1482: The prompt mechanism is rather complicated to provide flexibility,
1483: but the ordinary user need not understand the details of constructing
1484: personalized prompt strings.
1485: .Pp
1486: A percent sign followed by a single character is expanded
1487: according to what the following character is:
1488: .Bl -tag -width Ds
1489: .It %b Ns Ar X
1490: Replaced by the byte offset into the current input file.
1491: The b is followed by a single character (shown as
1492: .Ar X
1493: above) which specifies the line whose byte offset is to be used.
1494: If the character is a "t", the byte offset of the top line in the
1495: display is used,
1496: an "m" means use the middle line,
1497: a "b" means use the bottom line,
1498: a "B" means use the line just after the bottom line,
1.44 bentley 1499: and a "j" means use the "target" line, as specified by the
1500: .Fl j
1501: option.
1.4 jmc 1502: .It \&%B
1.1 millert 1503: Replaced by the size of the current input file.
1504: .It %c
1505: Replaced by the column number of the text appearing in the first
1506: column of the screen.
1507: .It %d Ns Ar X
1508: Replaced by the page number of a line in the input file.
1509: The line to be used is determined by the
1510: .Ar X ,
1511: as with the %b option.
1.4 jmc 1512: .It \&%D
1.1 millert 1513: Replaced by the number of pages in the input file,
1514: or equivalently, the page number of the last line in the input file.
1515: .It %E
1516: Replaced by the name of the editor (from the
1517: .Ev VISUAL
1518: environment variable, or the
1519: .Ev EDITOR
1520: environment variable if
1521: .Ev VISUAL
1522: is not defined).
1523: See the discussion of the LESSEDIT feature below.
1524: .It %f
1525: Replaced by the name of the current input file.
1.23 shadchin 1526: .It %F
1527: Replaced by the last component of the name of the current input file.
1.1 millert 1528: .It %i
1529: Replaced by the index of the current file in the list of
1530: input files.
1531: .It %l Ns Ar X
1532: Replaced by the line number of a line in the input file.
1533: The line to be used is determined by the
1534: .Ar X ,
1535: as with the %b option.
1536: .It %L
1537: Replaced by the line number of the last line in the input file.
1538: .It %m
1539: Replaced by the total number of input files.
1540: .It %p Ns Ar X
1541: Replaced by the percent into the current input file, based on byte offsets.
1542: The line used is determined by the
1543: .Ar X ,
1544: as with the %b option.
1.4 jmc 1545: .It \&%P Ns Ar X
1.1 millert 1546: Replaced by the percent into the current input file, based on line numbers.
1547: The line used is determined by the
1548: .Ar X ,
1549: as with the %b option.
1550: .It %s
1551: Same as %B.
1552: .It %t
1553: Causes any trailing spaces to be removed.
1554: Usually used at the end of the string, but may appear anywhere.
1555: .It %x
1556: Replaced by the name of the next input file in the list.
1557: .El
1558: .Pp
1559: If any item is unknown (for example, the file size if input is a pipe),
1560: a question mark is printed instead.
1561: .Pp
1562: The format of the prompt string can be changed depending on certain conditions.
1563: A question mark followed by a single character acts like an "IF":
1564: depending on the following character, a condition is evaluated.
1565: If the condition is true, any characters following the question mark
1566: and condition character, up to a period, are included in the prompt.
1567: If the condition is false, such characters are not included.
1568: A colon appearing between the question mark and the
1569: period can be used to establish an "ELSE": any characters between
1570: the colon and the period are included in the string, if and only if
1571: the IF condition is false.
1572: Condition characters (which follow a question mark) may be:
1573: .Bl -tag -width Ds
1574: .It ?a
1575: True if any characters have been included in the prompt so far.
1576: .It ?b Ns Ar X
1577: True if the byte offset of the specified line is known.
1578: .It ?B
1579: True if the size of the current input file is known.
1580: .It ?c
1581: True if the text is horizontally shifted (%c is not zero).
1582: .It ?d Ns Ar X
1583: True if the page number of the specified line is known.
1584: .It ?e
1585: True if at end-of-file.
1586: .It ?f
1587: True if there is an input filename
1588: (that is, if input is not a pipe).
1589: .It ?l Ns Ar X
1590: True if the line number of the specified line is known.
1591: .It ?L
1592: True if the line number of the last line in the file is known.
1593: .It ?m
1594: True if there is more than one input file.
1595: .It ?n
1596: True if this is the first prompt in a new input file.
1597: .It ?p Ns Ar X
1598: True if the percent into the current input file, based on byte offsets,
1599: of the specified line is known.
1600: .It ?P Ns Ar X
1601: True if the percent into the current input file, based on line numbers,
1602: of the specified line is known.
1603: .It ?s
1604: Same as "?B".
1605: .It ?x
1606: True if there is a next input file
1607: (that is, if the current input file is not the last one).
1608: .El
1609: .Pp
1610: Any characters other than the special ones
1611: (question mark, colon, period, percent, and backslash)
1612: become literally part of the prompt.
1613: Any of the special characters may be included in the prompt literally
1614: by preceding it with a backslash.
1615: .Pp
1616: Some examples:
1617: .Pp
1618: .Dl ?f%f:Standard input.
1619: .Pp
1620: This prompt prints the filename, if known;
1621: otherwise the string "Standard input".
1622: .Pp
1623: .Dl ?f%f .?ltLine %lt:?pt%pt\e%:?btByte %bt:-...
1624: .Pp
1625: This prompt would print the filename, if known.
1626: The filename is followed by the line number, if known,
1627: otherwise the percent if known, otherwise the byte offset if known.
1628: Otherwise, a dash is printed.
1629: Notice how each question mark has a matching period,
1630: and how the % after the %pt
1631: is included literally by escaping it with a backslash.
1632: .Pp
1633: .Dl ?n?f%f\ .?m(file\ %i\ of\ %m)\ ..?e(END)\ ?x-\ Next\e:\ %x..%t
1634: .Pp
1635: This prints the filename if this is the first prompt in a file,
1636: followed by the "file N of N" message if there is more
1637: than one input file.
1638: Then, if we are at end-of-file, the string "(END)" is printed
1639: followed by the name of the next file, if there is one.
1640: Finally, any trailing spaces are truncated.
1641: This is the default prompt.
1642: For reference, here are the defaults for
1.44 bentley 1643: the other two prompts
1644: .Po
1645: .Fl m
1646: and
1647: .Fl M
1648: respectively
1649: .Pc .
1.1 millert 1650: Each is broken into two lines here for readability only.
1651: .Bd -literal -offset indent
1.19 ray 1652: ?f%f\ .?m(file\ %i\ of\ %m)\ .?e(END)\ ?x-\ Next\e:\ %x.:
1.1 millert 1653: ?pB%pB\e%:byte\ %bB?s/%s...%t
1654:
1655: ?f%f\ .?n?m(file\ %i\ of\ %m)\ ..?ltlines\ %lt-%lb?L/%L.\ :
1656: byte\ %bB?s/%s.\ .?e(END)\ ?x-\ Next\e:\ %x.:?pB%pB\e%..%t
1657: .Ed
1658: .Pp
1659: And here is the default message produced by the = command:
1660: .Bd -literal -offset indent
1661: ?f%f\ .?m(file\ %i\ of\ %m)\ .?ltlines\ %lt-%lb?L/%L.\ .
1662: byte\ %bB?s/%s.\ ?e(END)\ :?pB%pB\e%..%t
1663: .Ed
1664: .Pp
1665: The prompt expansion features are also used for another purpose:
1666: if an environment variable
1667: .Ev LESSEDIT
1668: is defined, it is used as the command to be executed when the v command
1669: is invoked.
1670: The LESSEDIT string is expanded in the same way as the prompt strings.
1671: The default value for LESSEDIT is:
1672: .Pp
1673: .Dl %E\ ?lm+%lm.\ %f
1674: .Pp
1675: Note that this expands to the editor name, followed by a + and the
1676: line number, followed by the file name.
1677: If your editor does not accept the "+linenumber" syntax, or has other
1678: differences in invocation syntax, the
1679: .Ev LESSEDIT
1680: variable can be changed to modify this default.
1681: .Sh SECURITY
1682: When the environment variable
1683: .Ev LESSSECURE
1684: is set to 1,
1685: .Nm
1686: runs in a "secure" mode.
1687: This means these features are disabled:
1688: .Bl -tag -width Ds
1689: .It |
1690: The pipe command.
1691: .It :e
1692: The examine command.
1693: .It v
1694: The editing command.
1695: .It s -o
1696: Log files.
1.44 bentley 1697: .It Fl k
1.1 millert 1698: Use of lesskey files.
1.44 bentley 1699: .It Fl t
1.1 millert 1700: Use of tags files.
1701: .It " "
1702: Metacharacters in filenames, such as "*".
1703: .It " "
1704: Filename completion (TAB, ^L).
1705: .El
1.23 shadchin 1706: .Sh COMPATIBILITY WITH MORE
1707: If the environment variable
1708: .Ev LESS_IS_MORE
1709: is set to 1,
1710: or if the program is invoked via a file link named "more",
1711: .Nm
1712: behaves (mostly) in conformance with the POSIX "more" command specification.
1713: In this mode, less behaves differently in these ways:
1714: .Pp
1.43 jmc 1715: The sense of the
1716: .Fl c
1717: option is inverted:
1718: when
1719: .Xr more 1
1720: changes the display,
1721: the default is to scroll from the bottom of the screen,
1722: and the
1723: .Fl c
1724: option causes it to paint from the top line down.
1725: .Pp
1.37 jmc 1726: The
1727: .Fl e
1728: option works differently:
1729: it causes
1730: .Xr more 1
1731: to exit the first time it reaches EOF,
1732: not the second.
1.42 millert 1733: .Pp
1734: The
1735: .Fl i
1736: option acts like the
1737: .Fl I
1738: option.
1739: The normal behavior of the
1740: .Fl i
1741: option is unavailable in this mode.
1.23 shadchin 1742: .Pp
1.37 jmc 1743: The
1744: .Fl m
1745: option works differently:
1746: if it is not specified, the medium prompt is used;
1747: if it is specified, the short prompt is used.
1.23 shadchin 1748: .Pp
1.37 jmc 1749: The
1750: .Fl n
1751: option acts like the
1752: .Fl z
1753: option.
1754: The normal behavior of the
1755: .Fl n
1756: option is unavailable in this mode.
1757: .Pp
1758: The parameter to the
1759: .Fl p
1760: option is taken to be a
1.23 shadchin 1761: command rather than a search pattern.
1762: .Pp
1.43 jmc 1763: Options to suppress error messages when the terminal is dumb
1764: .Pq Fl d ,
1765: suppress highlighting of strings in search results
1766: .Pq Fl G ,
1767: and disable termcap initialization
1768: .Pq Fl X
1769: are on by default.
1770: .Pp
1.23 shadchin 1771: The
1772: .Ev LESS
1.39 jmc 1773: environment variables are ignored, and the
1.23 shadchin 1774: .Ev MORE
1775: environment variable is used in its place.
1.3 jmc 1776: .Sh ENVIRONMENT
1.1 millert 1777: Environment variables may be specified either in the system environment
1778: as usual, or in a
1779: .Xr lesskey 1
1780: file.
1781: If environment variables are defined in more than one place,
1782: variables defined in a local lesskey file take precedence over
1783: variables defined in the system environment, which take precedence
1784: over variables defined in the system-wide lesskey file.
1.38 jmc 1785: .Bl -tag -width LESSANSIENDCHARS
1.1 millert 1786: .It Ev COLUMNS
1787: Sets the number of columns on the screen.
1.41 jmc 1788: Takes precedence over the number of columns specified by the
1789: .Ev TERM
1790: variable,
1791: but may be overridden by window systems which support
1792: .Dv TIOCGWINSZ .
1.1 millert 1793: .It Ev EDITOR
1.41 jmc 1794: Specifies the default editor if
1795: .Ev VISUAL
1796: is not set.
1797: If neither are set,
1798: .Xr vi 1
1799: is used.
1.1 millert 1800: .It Ev HOME
1801: Name of the user's home directory
1802: (used to find a lesskey file).
1803: .It Ev LANG
1804: Language for determining the character set.
1805: .It Ev LC_CTYPE
1.52 schwarze 1806: The character encoding
1807: .Xr locale 1 .
1808: It decides which byte sequences form characters, what their display
1809: width is, and which characters are composing or combining characters.
1.1 millert 1810: .It Ev LESS
1811: Options which are passed to
1812: .Nm
1813: automatically.
1.38 jmc 1814: Command line options override the
1815: .Ev LESS
1816: environment variable.
1817: .Pp
1.44 bentley 1818: Some options like
1819: .Fl k
1820: require a string to follow the option letter.
1.38 jmc 1821: The string for that option is considered to end when a dollar sign ($) is found.
1822: For example, to separate a prompt value from any other options
1823: with dollar sign between them:
1824: .Pp
1825: .Dl LESS="-Ps--More--$-C -e"
1826: .Pp
1.44 bentley 1827: If the
1828: .Fl -use-backslash
1829: option appears earlier in the options, then
1.38 jmc 1830: a dollar sign or backslash may be included literally in an option string
1831: by preceding it with a backslash.
1.44 bentley 1832: If the
1833: .Fl -use-backslash
1834: option is not in effect, then backslashes are
1.38 jmc 1835: not treated specially, and there is no way to include a dollar sign
1836: in the option string.
1.1 millert 1837: .It Ev LESSANSIENDCHARS
1.23 shadchin 1838: Characters which may end an ANSI color escape sequence
1.1 millert 1839: (default "m").
1.23 shadchin 1840: .It Ev LESSANSIMIDCHARS
1841: Characters which may appear between the ESC character and the
1842: end character in an ANSI color escape sequence
1843: (default "0123456789;[?!"'#%()*+\ ").
1.1 millert 1844: .It Ev LESSBINFMT
1845: Format for displaying non-printable, non-control characters.
1846: .It Ev LESSCLOSE
1847: Command line to invoke the (optional) input-postprocessor.
1848: .It Ev LESSEDIT
1849: Editor prototype string (used for the v command).
1850: See discussion under
1851: .Sx PROMPTS .
1.23 shadchin 1852: .It Ev LESSHISTFILE
1853: Name of the history file used to remember search commands and
1854: shell commands between invocations of
1855: .Nm less .
1856: If set to "-" or "/dev/null", a history file is not used.
1.25 nicm 1857: The default is "-".
1.23 shadchin 1858: .It Ev LESSHISTSIZE
1859: The maximum number of commands to save in the history file.
1860: The default is 100.
1.1 millert 1861: .It Ev LESSKEY
1.54 ! naddy 1862: Name of the default
! 1863: .Xr lesskey 1
! 1864: file.
1.1 millert 1865: .It Ev LESSKEY_SYSTEM
1.54 ! naddy 1866: Name of the default system-wide
! 1867: .Xr lesskey 1
! 1868: file.
1.1 millert 1869: .It Ev LESSMETACHARS
1870: List of characters which are considered "metacharacters" by the shell.
1871: .It Ev LESSMETAESCAPE
1872: Prefix which
1873: .Nm
1874: will add before each metacharacter in a command sent to the shell.
1875: If LESSMETAESCAPE is an empty string, commands containing
1876: metacharacters will not be passed to the shell.
1877: .It Ev LESSOPEN
1878: Command line to invoke the (optional) input-preprocessor.
1879: .It Ev LESSSECURE
1880: Runs less in "secure" mode.
1881: See discussion under
1882: .Sx SECURITY .
1883: .It Ev LESSSEPARATOR
1884: String to be appended to a directory name in filename completion.
1.23 shadchin 1885: .It Ev LESSUTFBINFMT
1886: Format for displaying non-printable Unicode code points.
1887: .It Ev LESS_IS_MORE
1888: Emulate the
1889: .Xr more 1
1890: command.
1.1 millert 1891: .It Ev LINES
1892: Sets the number of lines on the screen.
1.41 jmc 1893: Takes precedence over the number of lines specified by the TERM variable,
1894: but may be overridden by window systems which support
1895: .Dv TIOCGWINSZ .
1.32 shadchin 1896: .It Ev MORE
1897: Options which are passed to
1898: .Nm
1.35 jmc 1899: automatically when running in
1.39 jmc 1900: .Xr more 1
1.32 shadchin 1901: compatible mode.
1.1 millert 1902: .It Ev SHELL
1.46 nicm 1903: The shell used to expand filenames.
1.1 millert 1904: .It Ev TERM
1.41 jmc 1905: Specifies the terminal type.
1906: Used by
1.1 millert 1907: .Nm
1.41 jmc 1908: to get the terminal characteristics necessary to manipulate the screen.
1.1 millert 1909: .It Ev VISUAL
1.41 jmc 1910: Specifies the default editor.
1911: If not set,
1.45 jmc 1912: .Ev EDITOR
1913: is used;
1.41 jmc 1914: if that is not set,
1915: .Xr vi 1
1916: is used.
1.1 millert 1917: .El
1918: .Sh SEE ALSO
1.37 jmc 1919: .Xr lesskey 1 ,
1920: .Xr more 1
1.7 jmc 1921: .Sh AUTHORS
1.38 jmc 1922: .An Mark Nudelman .
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