Annotation of src/usr.bin/sed/sed.1, Revision 1.63
1.63 ! jsg 1: .\" $OpenBSD: sed.1,v 1.62 2022/09/14 07:14:02 jmc Exp $
1.12 aaron 2: .\"
1.1 deraadt 3: .\" Copyright (c) 1992, 1993
4: .\" The Regents of the University of California. All rights reserved.
5: .\"
6: .\" This code is derived from software contributed to Berkeley by
7: .\" the Institute of Electrical and Electronics Engineers, Inc.
8: .\"
9: .\" Redistribution and use in source and binary forms, with or without
10: .\" modification, are permitted provided that the following conditions
11: .\" are met:
12: .\" 1. Redistributions of source code must retain the above copyright
13: .\" notice, this list of conditions and the following disclaimer.
14: .\" 2. Redistributions in binary form must reproduce the above copyright
15: .\" notice, this list of conditions and the following disclaimer in the
16: .\" documentation and/or other materials provided with the distribution.
1.17 millert 17: .\" 3. Neither the name of the University nor the names of its contributors
1.1 deraadt 18: .\" may be used to endorse or promote products derived from this software
19: .\" without specific prior written permission.
20: .\"
21: .\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22: .\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23: .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24: .\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25: .\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26: .\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27: .\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28: .\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29: .\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30: .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31: .\" SUCH DAMAGE.
32: .\"
33: .\" from: @(#)sed.1 8.2 (Berkeley) 12/30/93
34: .\"
1.63 ! jsg 35: .Dd $Mdocdate: September 14 2022 $
1.1 deraadt 36: .Dt SED 1
37: .Os
38: .Sh NAME
39: .Nm sed
40: .Nd stream editor
41: .Sh SYNOPSIS
42: .Nm sed
1.34 jmc 43: .Op Fl aEnru
1.46 jmc 44: .Op Fl i Ns Op Ar extension
1.1 deraadt 45: .Ar command
1.29 sobrado 46: .Op Ar
1.1 deraadt 47: .Nm sed
1.33 djm 48: .Op Fl aEnru
1.1 deraadt 49: .Op Fl e Ar command
50: .Op Fl f Ar command_file
1.45 jasper 51: .Op Fl i Ns Op Ar extension
1.29 sobrado 52: .Op Ar
1.1 deraadt 53: .Sh DESCRIPTION
54: The
1.8 aaron 55: .Nm
1.1 deraadt 56: utility reads the specified files, or the standard input if no files
57: are specified, modifying the input as specified by a list of commands.
58: The input is then written to the standard output.
59: .Pp
60: A single command may be specified as the first argument to
61: .Nm sed .
1.25 jmc 62: Multiple commands may be specified
63: separated by newlines or semicolons,
64: or by using the
1.1 deraadt 65: .Fl e
66: or
67: .Fl f
68: options.
69: All commands are applied to the input in the order they are specified
70: regardless of their origin.
71: .Pp
1.10 aaron 72: The options are as follows:
1.16 aaron 73: .Bl -tag -width Ds
1.1 deraadt 74: .It Fl a
75: The files listed as parameters for the
1.41 jmc 76: .Ic w
77: function or flag are created (or truncated) before any processing begins,
1.1 deraadt 78: by default.
79: The
80: .Fl a
81: option causes
1.8 aaron 82: .Nm
1.1 deraadt 83: to delay opening each file until a command containing the related
1.41 jmc 84: .Ic w
85: function or flag is applied to a line of input.
1.34 jmc 86: .It Fl E
87: Interpret regular expressions using POSIX extended regular expression syntax.
88: The default behaviour is to use POSIX basic regular expression syntax.
1.1 deraadt 89: .It Fl e Ar command
90: Append the editing commands specified by the
91: .Ar command
92: argument
93: to the list of commands.
94: .It Fl f Ar command_file
95: Append the editing commands found in the file
96: .Ar command_file
97: to the list of commands.
98: The editing commands should each be listed on a separate line.
1.46 jmc 99: .It Fl i Ns Op Ar extension
100: Edit files in place, saving backups with the specified
1.45 jasper 101: .Ar extension .
1.46 jmc 102: If a zero length
1.45 jasper 103: .Ar extension
104: is given, no backup will be saved.
1.46 jmc 105: It is not recommended to give a zero length
1.45 jasper 106: .Ar extension
1.46 jmc 107: when in place editing files, as it risks corruption or partial content
1.45 jasper 108: in situations where disk space is exhausted, etc.
1.57 martijn 109: In
110: .Fl i
111: mode, the hold space, line numbers, and ranges are reset between files.
1.33 djm 112: .It Fl r
1.34 jmc 113: An alias for
114: .Fl E ,
115: for compatibility with GNU sed.
1.1 deraadt 116: .It Fl n
117: By default, each line of input is echoed to the standard output after
118: all of the commands have been applied to it.
119: The
120: .Fl n
121: option suppresses this behavior.
1.26 ray 122: .It Fl u
123: Force output to be line buffered,
124: printing each line as it becomes available.
125: By default, output is line buffered when standard output is a terminal
126: and block buffered otherwise.
127: See
1.47 tedu 128: .Xr setvbuf 3
1.26 ray 129: for a more detailed explanation.
1.1 deraadt 130: .El
131: .Pp
132: The form of a
1.8 aaron 133: .Nm
1.1 deraadt 134: command is as follows:
1.21 jmc 135: .Pp
1.1 deraadt 136: .Dl [address[,address]]function[arguments]
1.21 jmc 137: .Pp
1.1 deraadt 138: Whitespace may be inserted before the first address and the function
139: portions of the command.
140: .Pp
141: Normally,
1.8 aaron 142: .Nm
1.1 deraadt 143: cyclically copies a line of input, not including its terminating newline
144: character, into a
1.21 jmc 145: .Em pattern space ,
1.1 deraadt 146: (unless there is something left after a
1.37 jmc 147: .Ic D
1.1 deraadt 148: function),
149: applies all of the commands with addresses that select that pattern space,
150: copies the pattern space to the standard output, appending a newline, and
151: deletes the pattern space.
152: .Pp
153: Some of the functions use a
1.21 jmc 154: .Em hold space
1.1 deraadt 155: to save all or part of the pattern space for subsequent retrieval.
1.21 jmc 156: .Sh SED ADDRESSES
1.1 deraadt 157: An address is not required, but if specified must be a number (that counts
158: input lines
1.21 jmc 159: cumulatively across input files), a dollar character
1.8 aaron 160: .Pq Ql $
1.55 schwarze 161: that addresses the last line of input, or a context address,
162: which is a regular expression preceded and followed by a delimiter.
1.56 martijn 163: The delimiter can be any character except a newline or a backslash.
1.55 schwarze 164: Unless it is a slash, the opening delimiter needs to be escaped with
165: a backslash.
1.1 deraadt 166: .Pp
167: A command line with no addresses selects every pattern space.
168: .Pp
169: A command line with one address selects all of the pattern spaces
170: that match the address.
171: .Pp
172: A command line with two addresses selects the inclusive range from
173: the first pattern space that matches the first address through the next
174: pattern space that matches the second.
1.62 jmc 175: If the second address is a number less than or equal to the line number
176: first selected, only the first address is selected.
1.1 deraadt 177: Starting at the first line following the selected range,
1.8 aaron 178: .Nm
1.1 deraadt 179: starts looking again for the first address.
180: .Pp
181: Editing commands can be applied to non-selected pattern spaces by use
182: of the exclamation character
1.18 jmc 183: .Pq Ql \&!
1.1 deraadt 184: function.
1.21 jmc 185: .Sh SED REGULAR EXPRESSIONS
1.34 jmc 186: By default,
1.8 aaron 187: .Nm
1.23 jmc 188: regular expressions are basic regular expressions
189: .Pq BREs .
1.34 jmc 190: Extended regular expressions are supported using the
191: .Fl E
192: and
193: .Fl r
194: options.
1.23 jmc 195: See
1.19 jmc 196: .Xr re_format 7
1.23 jmc 197: for more information on regular expressions.
1.1 deraadt 198: In addition,
1.8 aaron 199: .Nm
1.23 jmc 200: has the following two additions to BREs:
1.21 jmc 201: .Pp
1.1 deraadt 202: .Bl -enum -compact
203: .It
1.55 schwarze 204: The character delimiting the regular expression
205: can be used inside the regular expression by prepending a backslash
206: or by including it in a character class.
207: For example, in the context address \ex\ex[xy]x, the RE delimiter
1.1 deraadt 208: is an
1.8 aaron 209: .Sq x
1.55 schwarze 210: and the other
1.8 aaron 211: .Sq x
1.55 schwarze 212: characters stand for themselves, so that the regular expression is
213: .Dq x[xy] .
1.21 jmc 214: .Pp
1.1 deraadt 215: .It
216: The escape sequence \en matches a newline character embedded in the
217: pattern space.
218: You can't, however, use a literal newline character in an address or
219: in the substitute command.
220: .El
221: .Pp
222: One special feature of
1.8 aaron 223: .Nm
1.1 deraadt 224: regular expressions is that they can default to the last regular
225: expression used.
1.13 aaron 226: If a regular expression is empty, i.e., just the delimiter characters
1.1 deraadt 227: are specified, the last regular expression encountered is used instead.
228: The last regular expression is defined as the last regular expression
229: used as part of an address or substitute command, and at run-time, not
230: compile-time.
231: For example, the command
232: .Dq /abc/s//XXX/
233: will substitute
234: .Dq XXX
235: for the pattern
236: .Dq abc .
1.21 jmc 237: .Sh SED FUNCTIONS
1.1 deraadt 238: In the following list of commands, the maximum number of permissible
239: addresses for each command is indicated by [0addr], [1addr], or [2addr],
240: representing zero, one, or two addresses.
241: .Pp
242: The argument
1.37 jmc 243: .Ar text
1.1 deraadt 244: consists of one or more lines.
245: To embed a newline in the text, precede it with a backslash.
246: Other backslashes in text are deleted and the following character
247: taken literally.
248: .Pp
249: The
1.40 jmc 250: .Ic r
1.1 deraadt 251: and
1.40 jmc 252: .Ic w
253: functions,
254: as well as the
255: .Cm w
256: flag to the
257: .Ic s
258: function,
1.52 martijn 259: take a
1.40 jmc 260: .Ar file
261: parameter,
262: which should be separated from the function or flag by whitespace.
263: Files are created
264: (or their contents truncated)
265: before any input processing begins.
1.1 deraadt 266: .Pp
267: The
1.40 jmc 268: .Ic b ,
269: .Ic r ,
270: .Ic s ,
271: .Ic t ,
272: .Ic w ,
273: .Ic y ,
1.1 deraadt 274: and
1.40 jmc 275: .Ic \&:
1.1 deraadt 276: functions all accept additional arguments.
1.40 jmc 277: The synopses below indicate which arguments have to be separated from
1.9 aaron 278: the function letters by whitespace characters.
1.1 deraadt 279: .Pp
1.58 schwarze 280: The
281: .Ic a ,
282: .Ic c ,
283: .Ic i ,
284: .Ic r ,
285: and
286: .Ic w
287: functions cannot be followed by another command separated with a semicolon.
288: The
289: .Ar text
290: and
291: .Ar file
292: arguments may contain semicolon characters.
293: .Pp
1.41 jmc 294: Functions can be combined to form a
295: .Em function list ,
296: a list of
1.8 aaron 297: .Nm
1.44 schwarze 298: functions each followed by a newline, as follows:
1.1 deraadt 299: .Bd -literal -offset indent
300: { function
301: function
302: ...
303: function
304: }
305: .Ed
306: .Pp
1.44 schwarze 307: The braces can be preceded and followed by whitespace.
308: The functions can be preceded by whitespace as well.
1.38 jmc 309: .Pp
1.40 jmc 310: Functions and function lists may be preceded by an exclamation mark,
1.38 jmc 311: in which case they are applied only to lines that are
312: .Em not
313: selected by the addresses.
1.37 jmc 314: .Bl -tag -width Ds
1.51 martijn 315: .It [2addr] Ns Ar function-list
1.15 aaron 316: Execute
1.37 jmc 317: .Ar function-list
1.15 aaron 318: only when the pattern space is selected.
1.51 martijn 319: .It Xo [1addr] Ns Ic a Ns \e
1.37 jmc 320: .br
321: .Ar text
322: .Xc
1.1 deraadt 323: Write
1.37 jmc 324: .Ar text
1.1 deraadt 325: to standard output immediately before each attempt to read a line of input,
326: whether by executing the
1.37 jmc 327: .Ic N
1.1 deraadt 328: function or by beginning a new cycle.
1.37 jmc 329: .It [2addr] Ns Ic b Bq Ar label
1.1 deraadt 330: Branch to the
1.37 jmc 331: .Ic \&:
332: function with the specified
333: .Ar label .
1.1 deraadt 334: If the label is not specified, branch to the end of the script.
1.51 martijn 335: .It Xo [2addr] Ns Ic c Ns \e
1.37 jmc 336: .br
337: .Ar text
338: .Xc
1.1 deraadt 339: Delete the pattern space.
340: With 0 or 1 address or at the end of a 2-address range,
1.37 jmc 341: .Ar text
1.1 deraadt 342: is written to the standard output.
1.37 jmc 343: .It [2addr] Ns Ic d
1.1 deraadt 344: Delete the pattern space and start the next cycle.
1.37 jmc 345: .It [2addr] Ns Ic D
1.1 deraadt 346: Delete the initial segment of the pattern space through the first
347: newline character and start the next cycle.
1.37 jmc 348: .It [2addr] Ns Ic g
1.1 deraadt 349: Replace the contents of the pattern space with the contents of the
350: hold space.
1.37 jmc 351: .It [2addr] Ns Ic G
1.1 deraadt 352: Append a newline character followed by the contents of the hold space
353: to the pattern space.
1.37 jmc 354: .It [2addr] Ns Ic h
1.1 deraadt 355: Replace the contents of the hold space with the contents of the
356: pattern space.
1.37 jmc 357: .It [2addr] Ns Ic H
1.1 deraadt 358: Append a newline character followed by the contents of the pattern space
359: to the hold space.
1.51 martijn 360: .It Xo [1addr] Ns Ic i Ns \e
1.37 jmc 361: .br
362: .Ar text
363: .Xc
1.1 deraadt 364: Write
1.37 jmc 365: .Ar text
1.1 deraadt 366: to the standard output.
1.37 jmc 367: .It [2addr] Ns Ic l
1.1 deraadt 368: (The letter ell.)
369: Write the pattern space to the standard output in a visually unambiguous
370: form.
371: This form is as follows:
1.21 jmc 372: .Pp
1.1 deraadt 373: .Bl -tag -width "carriage-returnXX" -offset indent -compact
374: .It backslash
1.3 deraadt 375: \e\e
1.1 deraadt 376: .It alert
377: \ea
1.31 millert 378: .It backspace
379: \eb
1.1 deraadt 380: .It form-feed
381: \ef
382: .It carriage-return
383: \er
384: .It tab
385: \et
386: .It vertical tab
387: \ev
388: .El
389: .Pp
1.15 aaron 390: Non-printable characters are written as three-digit octal numbers (with a
1.1 deraadt 391: preceding backslash) for each byte in the character (most significant byte
392: first).
393: Long lines are folded, with the point of folding indicated by displaying
394: a backslash followed by a newline.
395: The end of each line is marked with a
1.8 aaron 396: .Ql $ .
1.37 jmc 397: .It [2addr] Ns Ic n
1.1 deraadt 398: Write the pattern space to the standard output if the default output has
399: not been suppressed, and replace the pattern space with the next line of
400: input.
1.37 jmc 401: .It [2addr] Ns Ic N
1.1 deraadt 402: Append the next line of input to the pattern space, using an embedded
403: newline character to separate the appended material from the original
404: contents.
405: Note that the current line number changes.
1.37 jmc 406: .It [2addr] Ns Ic p
1.1 deraadt 407: Write the pattern space to standard output.
1.37 jmc 408: .It [2addr] Ns Ic P
1.39 jmc 409: Write the pattern space, up to the first newline character,
410: to the standard output.
1.37 jmc 411: .It [1addr] Ns Ic q
1.57 martijn 412: Branch to the end of the script and quit without starting a new cycle or file.
1.37 jmc 413: .It [1addr] Ns Ic r Ar file
1.1 deraadt 414: Copy the contents of
1.37 jmc 415: .Ar file
1.1 deraadt 416: to the standard output immediately before the next attempt to read a
417: line of input.
418: If
1.37 jmc 419: .Ar file
1.1 deraadt 420: cannot be read for any reason, it is silently ignored and no error
421: condition is set.
1.37 jmc 422: .It [2addr] Ns Ic s Ns / Ns Ar RE Ns / Ns Ar replacement Ns / Ns Ar flags
423: Substitute the
424: .Ar replacement
425: string for the first instance of the regular expression
426: .Ar RE
427: in the pattern space.
1.1 deraadt 428: Any character other than backslash or newline can be used instead of
1.37 jmc 429: a slash to delimit the regular expression and the replacement.
1.59 jmc 430: Also see the section about
1.55 schwarze 431: .Sx SED REGULAR EXPRESSIONS .
1.1 deraadt 432: .Pp
433: An ampersand
1.8 aaron 434: .Pq Ql &
1.37 jmc 435: appearing in the replacement is replaced by the string matching the
436: regular expression.
1.1 deraadt 437: The string
1.8 aaron 438: .Ql \e# ,
1.1 deraadt 439: where
1.8 aaron 440: .Ql #
1.1 deraadt 441: is a digit, is replaced by the text matched
442: by the corresponding backreference expression (see
1.14 aaron 443: .Xr re_format 7 ) .
1.1 deraadt 444: .Pp
1.56 martijn 445: All other instances of a backslash will print the literal character
446: following it.
447: Using a backslash before any other character other than
448: .Ql & ,
449: .Ql \e ,
450: digit, newline
451: .Pq ascii 0x0a ,
452: and the delimiter is unspecified and might not be portable to other
453: implementations of
454: .Nm .
1.1 deraadt 455: .Pp
456: The value of
1.37 jmc 457: .Ar flags
1.1 deraadt 458: in the substitute function is zero or more of the following:
459: .Bl -tag -width "XXXXXX" -offset indent
1.49 schwarze 460: .It Ar N
461: Make the substitution only for the
462: .Ar N Ap th
463: occurrence of the regular expression in the pattern space, where
464: .Ar N
465: is a positive integer starting with
466: .Cm 1 No ... Cm 9 .
1.37 jmc 467: .It Cm g
1.1 deraadt 468: Make the substitution for all non-overlapping matches of the
469: regular expression, not just the first one.
1.37 jmc 470: .It Cm p
1.1 deraadt 471: Write the pattern space to standard output if a replacement was made.
472: If the replacement string is identical to that which it replaces, it
473: is still considered to have been a replacement.
1.37 jmc 474: .It Cm w Ar file
1.1 deraadt 475: Append the pattern space to
1.37 jmc 476: .Ar file
1.1 deraadt 477: if a replacement was made.
478: If the replacement string is identical to that which it replaces, it
479: is still considered to have been a replacement.
480: .El
1.37 jmc 481: .It [2addr] Ns Ic t Bq Ar label
1.1 deraadt 482: Branch to the
1.37 jmc 483: .Ic \&:
484: function bearing the
485: .Ar label
486: if any substitutions have been made since the
1.1 deraadt 487: most recent reading of an input line or execution of a
1.37 jmc 488: .Ic t
1.1 deraadt 489: function.
490: If no label is specified, branch to the end of the script.
1.37 jmc 491: .It [2addr] Ns Ic w Ar file
1.1 deraadt 492: Append the pattern space to the
1.37 jmc 493: .Ar file .
494: .It [2addr] Ns Ic x
1.1 deraadt 495: Swap the contents of the pattern and hold spaces.
1.37 jmc 496: .It [2addr] Ns Ic y Ns / Ns Ar string1 Ns / Ns Ar string2 Ns /
1.1 deraadt 497: Replace all occurrences of characters in
1.37 jmc 498: .Ar string1
1.1 deraadt 499: in the pattern space with the corresponding characters from
1.37 jmc 500: .Ar string2 .
1.1 deraadt 501: Any character other than a backslash or newline can be used instead of
502: a slash to delimit the strings.
1.53 martijn 503: .Pp
1.1 deraadt 504: Within
1.37 jmc 505: .Ar string1
1.1 deraadt 506: and
1.37 jmc 507: .Ar string2 ,
1.53 martijn 508: a backslash followed by another backslash
509: is replaced by a single backslash,
510: a backslash followed by an
511: .Sq n
512: is replaced by a newline character,
513: and a backslash followed by the delimiting character
514: is replaced by that character,
515: causing it to be treated literally,
516: with the exception of the
1.8 aaron 517: .Sq n
1.53 martijn 518: character,
519: which will still be treated like a newline character.
520: It is an error for a backslash to not be followed by another backslash,
521: .Sq n ,
522: or the delimiting character,
523: or for
524: .Ar string1
525: to contain repeating characters.
1.37 jmc 526: .It [0addr] Ns Ic \&: Ns Ar label
527: This function does nothing; it bears a
528: .Ar label
529: to which the
530: .Ic b
1.1 deraadt 531: and
1.37 jmc 532: .Ic t
1.1 deraadt 533: commands may branch.
1.37 jmc 534: .It [1addr] Ns Ic =
1.15 aaron 535: Write the line number to the standard output followed by a newline character.
1.1 deraadt 536: .It [0addr]
537: Empty lines are ignored.
1.37 jmc 538: .It [0addr] Ns Ic #
1.1 deraadt 539: The
1.8 aaron 540: .Ql #
1.1 deraadt 541: and the remainder of the line are ignored (treated as a comment), with
542: the single exception that if the first two characters in the file are
1.8 aaron 543: .Ql #n ,
1.1 deraadt 544: the default output is suppressed.
545: This is the same as specifying the
546: .Fl n
547: option on the command line.
1.48 bentley 548: .El
549: .Sh ENVIRONMENT
550: .Bl -tag -width COLUMNS
551: .It Ev COLUMNS
552: If set to a positive integer,
553: output from the
554: .Ic l
555: function is formatted to the given width in columns.
556: Otherwise,
557: .Nm
1.51 martijn 558: defaults to the terminal width, or 80 columns if the output is not a terminal.
1.1 deraadt 559: .El
1.36 jmc 560: .Sh EXIT STATUS
1.24 jmc 561: .Ex -std sed
1.1 deraadt 562: .Sh SEE ALSO
563: .Xr awk 1 ,
564: .Xr ed 1 ,
565: .Xr grep 1 ,
566: .Xr re_format 7
1.60 jsg 567: .Rs
568: .\" 4.4BSD USD:15
569: .%A Lee E. McMahon
570: .%I AT&T Bell Laboratories
571: .%T SED \(em A Non-interactive Text Editor
572: .%R Computing Science Technical Report
573: .%N 77
574: .%D January 1979
575: .Re
1.1 deraadt 576: .Sh STANDARDS
577: The
1.8 aaron 578: .Nm
1.25 jmc 579: utility is compliant with the
1.32 jmc 580: .St -p1003.1-2008
1.1 deraadt 581: specification.
1.25 jmc 582: .Pp
1.26 ray 583: The flags
1.45 jasper 584: .Op Fl aEiru
1.27 jmc 585: are extensions to that specification.
1.25 jmc 586: .Pp
1.58 schwarze 587: Following the
588: .Ic b ,
589: .Ic t ,
590: or
591: .Ic \&:
592: commands with a semicolon and another command is an extension to the
593: specification.
594: .Pp
1.25 jmc 595: The use of newlines to separate multiple commands on the command line
596: is non-portable;
597: the use of newlines to separate multiple commands within a command file
598: .Pq Fl f Ar command_file
599: is portable.
1.11 aaron 600: .Sh HISTORY
601: A
602: .Nm
1.61 jsg 603: command first appeared outside of Bell Labs in PWB/UNIX 1.0.
604: It was replaced in
605: .Bx 4.4 .
606: .Sh AUTHORS
607: .An Lee McMahon
608: wrote the original implementation at the
1.63 ! jsg 609: Bell Labs Computing Science Research Center.
1.61 jsg 610: The
611: .Bx 4.4
612: implementation was written by
613: .An Diomidis Spinellis .