Annotation of src/usr.bin/diff/diff.1, Revision 1.22
1.22 ! jmc 1: .\" $OpenBSD: diff.1,v 1.21 2003/09/07 18:50:58 jmc Exp $
1.6 millert 2: .\"
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1.1 deraadt 29: .\"
1.2 deraadt 30: .\" @(#)diff.1 8.1 (Berkeley) 6/30/93
31: .\"
1.16 millert 32: .Dd July 21, 2003
1.1 deraadt 33: .Dt DIFF 1
1.5 jmc 34: .Os
1.1 deraadt 35: .Sh NAME
36: .Nm diff
37: .Nd differential file and directory comparator
38: .Sh SYNOPSIS
39: .Nm diff
1.19 otto 40: .Op Fl abdilqtTw
1.6 millert 41: .Oo
42: .Fl c | Fl e | Fl f |
1.9 millert 43: .Fl n | Fl u
1.6 millert 44: .Oc
1.16 millert 45: .Op Fl L Ar label
1.6 millert 46: .Ar file1 file2
47: .Nm diff
1.19 otto 48: .Op Fl abdilqtTw
1.16 millert 49: .Op Fl L Ar label
50: .Fl C Ar number
1.6 millert 51: .Ar file1 file2
52: .Nm diff
1.19 otto 53: .Op Fl abdilqtw
1.16 millert 54: .Fl D Ar string
1.1 deraadt 55: .Ar file1 file2
56: .Nm diff
1.19 otto 57: .Op Fl abdilqtTw
1.16 millert 58: .Op Fl L Ar label
59: .Fl U Ar number
1.1 deraadt 60: .Ar file1 file2
61: .Nm diff
1.21 jmc 62: .Op Fl abdilNPqtTw
1.6 millert 63: .Oo
64: .Fl c | Fl e | Fl f |
1.9 millert 65: .Fl n | Fl u
1.6 millert 66: .Oc
1.11 millert 67: .Bk -words
1.16 millert 68: .Op Fl L Ar label
1.1 deraadt 69: .Op Fl r
70: .Op Fl s
1.6 millert 71: .Op Fl S Ar name
1.11 millert 72: .Op Fl X Ar file
73: .Op Fl x Ar pattern
74: .Ek
1.1 deraadt 75: .Ar dir1 dir2
76: .Sh DESCRIPTION
77: The
1.5 jmc 78: .Nm
1.1 deraadt 79: utility compares the contents of
80: .Ar file1
81: and
82: .Ar file2
83: and writes to the standard output the list of changes necessary to
84: convert one file into the other.
85: No output is produced if the files are identical.
86: .Pp
1.22 ! jmc 87: Output options (mutually exclusive):
1.2 deraadt 88: .Bl -tag -width Ds
89: .It Fl c
1.6 millert 90: Produces a diff with 3 lines of context.
1.1 deraadt 91: With
92: .Fl c
93: the output format is modified slightly:
1.21 jmc 94: the output begins with identification of the files involved and
1.1 deraadt 95: their creation dates and then each change is separated
1.21 jmc 96: by a line with fifteen *'s.
1.1 deraadt 97: The lines removed from
98: .Ar file1
1.5 jmc 99: are marked with
100: .Sq \-\ \& ;
101: those added to
1.1 deraadt 102: .Ar file2
1.5 jmc 103: are marked
104: .Sq \+\ \& .
105: Lines which are changed from one file to the other are marked in
106: both files with
107: .Sq !\ \& .
1.19 otto 108: Changes which lie within 3 lines of each other are grouped together on
109: output.
1.2 deraadt 110: .It Fl e
1.5 jmc 111: Produces output in a form suitable as input for the editor utility,
1.1 deraadt 112: .Xr ed 1 ,
113: which can then be used to convert file1 into file2.
114: .Pp
115: Extra commands are added to the output when comparing directories with
116: .Fl e ,
117: so that the result is a
1.5 jmc 118: .Xr sh 1
1.1 deraadt 119: script for converting text files which are common to the two directories
120: from their state in
121: .Ar dir1
122: to their state in
123: .Ar dir2 .
1.2 deraadt 124: .It Fl f
1.5 jmc 125: Identical output to that of the
1.1 deraadt 126: .Fl e
1.5 jmc 127: flag, but in reverse order.
128: It cannot be digested by
1.1 deraadt 129: .Xr ed 1 .
1.2 deraadt 130: .It Fl n
1.5 jmc 131: Produces a script similar to that of
1.1 deraadt 132: .Fl e ,
133: but in the opposite order and with a count of changed lines on each
1.5 jmc 134: insert or delete command.
135: This is the form used by
136: .Xr rcsdiff 1 .
1.13 millert 137: .It Fl q
138: Just print a line when the files differ.
139: Does not output a list of changes.
1.6 millert 140: .It Fl u
141: Produces a
142: .Em unified
143: diff with 3 lines of context.
144: A unified diff is similar to the context diff produced by the
145: .Fl c
146: option.
147: However, unlike with
148: .Fl c ,
149: all lines to be changed (added and/or removed) are present in
150: a single section.
151: .It Fl C Ar number
152: Like
153: .Fl c
154: but produces a diff with
155: .Ar number
156: lines of context.
157: .It Fl D Ar string
1.5 jmc 158: Creates a merged version of
1.1 deraadt 159: .Ar file1
160: and
161: .Ar file2
162: on the standard output, with C preprocessor controls included so that
163: a compilation of the result without defining
164: .Ar string
1.5 jmc 165: is equivalent to compiling
1.1 deraadt 166: .Ar file1 ,
167: while defining
168: .Ar string
169: will yield
170: .Ar file2 .
1.6 millert 171: .It Fl U Ar number
172: Like
173: .Fl u
174: but produces a diff with
175: .Ar number
176: lines of context.
1.2 deraadt 177: .El
1.1 deraadt 178: .Pp
179: Comparison options:
1.2 deraadt 180: .Bl -tag -width Ds
1.11 millert 181: .It Fl a
182: Treat all files as ASCII.
1.2 deraadt 183: .It Fl b
1.5 jmc 184: Causes trailing blanks (spaces and tabs) to be ignored, and other
1.1 deraadt 185: strings of blanks to compare equal.
1.22 ! jmc 186: .It Fl d
! 187: Try very hard to produce a diff as small as possible.
! 188: This may consume a lot of processing power and memory when processing
! 189: large files with many changes.
1.16 millert 190: .It Fl i
191: Ignores the case of letters.
192: E.g.,
193: .Dq A
194: will compare equal to
195: .Dq a .
1.14 millert 196: .It Fl l
197: Long output format; each text file
198: .Nm diff Ns \'d
199: is piped through
200: .Xr pr 1
201: to paginate it;
202: other differences are remembered and summarized
203: after all text file differences are reported.
1.16 millert 204: .It Fl L Ar label
205: Print
206: .Ar label
207: instead of the first file name and time in the context or unified diff header.
1.2 deraadt 208: .It Fl t
1.5 jmc 209: Will expand tabs in output lines.
210: Normal or
1.1 deraadt 211: .Fl c
212: output adds character(s) to the front of each line which may screw up
213: the indentation of the original source lines and make the output listing
1.5 jmc 214: difficult to interpret.
215: This option will preserve the original source's indentation.
1.16 millert 216: .It Fl T
217: Print a tab rather than a space before the rest of the line for the
218: normal, context or unified output formats.
219: This makes the alignment of tabs in the line consistent.
1.2 deraadt 220: .It Fl w
1.5 jmc 221: Is similar to
1.1 deraadt 222: .Fl b
1.5 jmc 223: but causes whitespace (blanks and tabs) to be totally ignored.
224: E.g.,
225: .Dq if (\ \&a == b \&)
226: will compare equal to
227: .Dq if(a==b) .
1.2 deraadt 228: .El
1.1 deraadt 229: .Pp
230: Directory comparison options:
1.2 deraadt 231: .Bl -tag -width Ds
1.11 millert 232: .It Fl N
233: If a file is found in only one directory, act as if it was found in the
234: other directory too but was of zero size.
1.12 millert 235: .It Fl P
236: If a file is found only in
237: .Ar dir2 ,
238: act as if it was found in
239: .Ar dir1
240: too but was of zero size.
1.2 deraadt 241: .It Fl r
1.5 jmc 242: Causes application of
243: .Nm
1.1 deraadt 244: recursively to common subdirectories encountered.
1.2 deraadt 245: .It Fl s
1.5 jmc 246: Causes
247: .Nm
1.1 deraadt 248: to report files which are the same, which are otherwise not mentioned.
1.6 millert 249: .It Fl S Ar name
1.5 jmc 250: Re-starts a directory
251: .Nm
252: in the middle, beginning with file
1.1 deraadt 253: .Ar name .
1.11 millert 254: .It Fl X Ar file
255: Exclude files and subdirectories from comparison whose basenames match
256: lines in
257: .Ar file .
258: Multiple
259: .Fl X
260: options may be specified.
261: .It Fl x Ar pattern
262: Exclude files and subdirectories from comparison whose basenames match
263: .Ar pattern .
264: Patterns are matched using shell-style globbing via
265: .Xr fnmatch 3 .
266: Multiple
267: .Fl x
268: options may be specified.
1.2 deraadt 269: .El
1.1 deraadt 270: .Pp
271: If both arguments are directories,
1.5 jmc 272: .Nm
1.1 deraadt 273: sorts the contents of the directories by name, and then runs the
274: regular file
1.5 jmc 275: .Nm
1.1 deraadt 276: algorithm, producing a change list,
277: on text files which are different.
278: Binary files which differ,
279: common subdirectories, and files which appear in only one directory
280: are described as such.
281: .Pp
282: If only one of
283: .Ar file1
284: and
285: .Ar file2
286: is a directory,
1.5 jmc 287: .Nm
1.1 deraadt 288: is applied to the non-directory file and the file contained in
289: the directory file with a filename that is the same as the
290: last component of the non-directory file.
291: .Pp
1.2 deraadt 292: If either
1.1 deraadt 293: .Ar file1
294: or
295: .Ar file2
296: is
1.2 deraadt 297: .Sq Fl ,
1.1 deraadt 298: the standard input is
299: used in its place.
300: .Ss Output Style
301: The default (without
302: .Fl e ,
303: .Fl c ,
304: or
305: .Fl n
1.5 jmc 306: .\" -C
1.1 deraadt 307: options)
308: output contains lines of these forms, where
309: .Va XX , YY , ZZ , QQ
310: are line numbers respective of file order.
311: .Pp
1.2 deraadt 312: .Bl -tag -width "XX,YYcZZ,QQ" -compact
313: .It Li XX Ns Ic a Ns Li YY
1.1 deraadt 314: At (the end of) line
315: .Va XX
316: of
317: .Ar file1 ,
318: append the contents
319: of line
320: .Va YY
321: of
322: .Ar file2
323: to make them equal.
1.2 deraadt 324: .It Li XX Ns Ic a Ns Li YY,ZZ
1.1 deraadt 325: Same as above, but append the range of lines,
326: .Va YY
327: through
328: .Va ZZ
329: of
330: .Ar file2
331: to line
332: .Va XX
333: of file1.
1.2 deraadt 334: .It Li XX Ns Ic d Ns Li YY
1.1 deraadt 335: At line
336: .Va XX
337: delete
1.5 jmc 338: the line.
339: The value
1.1 deraadt 340: .Va YY
1.5 jmc 341: tells to which line the change would bring
1.1 deraadt 342: .Ar file1
343: in line with
344: .Ar file1 .
1.2 deraadt 345: .It Li XX,YY Ns Ic d Ns Li ZZ
1.1 deraadt 346: Delete the range of lines
347: .Va XX
348: through
349: .Va YY
350: in
351: .Ar file1 .
1.2 deraadt 352: .It Li XX Ns Ic c Ns Li YY
1.1 deraadt 353: Change the line
354: .Va XX
355: in
356: .Ar file1
357: to the line
358: .Va YY
359: in
1.5 jmc 360: .Ar file2 .
1.2 deraadt 361: .It Li XX,YY Ns Ic c Ns Li ZZ
1.1 deraadt 362: Replace the range of specified lines with the line
363: .Va ZZ .
1.2 deraadt 364: .It Li XX,YY Ns Ic c Ns Li ZZ,QQ
1.1 deraadt 365: Replace the range
1.2 deraadt 366: .Va XX , Ns YY
1.1 deraadt 367: from
368: .Ar file1
369: with the range
1.2 deraadt 370: .Va ZZ , Ns QQ
1.1 deraadt 371: from
372: .Ar file2 .
1.2 deraadt 373: .El
1.1 deraadt 374: .Pp
375: These lines resemble
376: .Xr ed 1
377: subcommands to convert
378: .Ar file1
379: into
380: .Ar file2 .
381: The line numbers before the action letters pertain to
382: .Ar file1 ;
383: those after pertain to
384: .Ar file2 .
385: Thus, by exchanging
386: .Ic a
387: for
388: .Ic d
389: and reading the line in reverse order, one can also
390: determine how to convert
391: .Ar file2
392: into
393: .Ar file1 .
394: As in
395: .Xr ed 1 ,
396: identical
397: pairs (where num1 = num2) are abbreviated as a single
398: number.
399: .Sh ENVIRONMENT
1.2 deraadt 400: .Bl -tag -width TMPDIR
401: .It Ev TMPDIR
1.1 deraadt 402: If the environment variable
403: .Ev TMPDIR
404: exists,
1.5 jmc 405: .Nm
1.2 deraadt 406: will use the directory specified by
1.1 deraadt 407: .Ev TMPDIR
1.2 deraadt 408: as the temporary directory.
409: .El
1.1 deraadt 410: .Sh FILES
1.17 millert 411: .Bl -tag -width /tmp/diff.XXXXXXXX -compact
412: .It Pa /tmp/diff.XXXXXXXX
413: Temporary file used when comparing a device or the standard input.
414: Note that the temporary file is unlinked as soon as it is created
415: so it will not show up in a directory listing.
1.2 deraadt 416: .El
1.1 deraadt 417: .Sh DIAGNOSTICS
418: The
1.5 jmc 419: .Nm
1.1 deraadt 420: utility exits with one of the following values:
1.2 deraadt 421: .Pp
422: .Bl -tag -width Ds -compact -offset indent
423: .It \&0
1.1 deraadt 424: No differences were found.
1.2 deraadt 425: .It \&1
1.1 deraadt 426: Differences were found.
1.5 jmc 427: .It \*[Gt]\&1
1.1 deraadt 428: An error occurred.
1.2 deraadt 429: .El
1.5 jmc 430: .Sh SEE ALSO
431: .Xr cmp 1 ,
432: .Xr comm 1 ,
433: .Xr diff3 1 ,
1.11 millert 434: .Xr ed 1 ,
1.14 millert 435: .Xr pr 1 ,
1.11 millert 436: .Xr fnmatch 3
1.15 millert 437: .Sh STANDARDS
438: The
439: .Nm
440: utility is expected to be a superset of the
441: .St -p1003.1-01
442: specification.
1.5 jmc 443: .Sh HISTORY
444: A
445: .Nm
446: command appeared in
447: .At v6 .
1.1 deraadt 448: .Sh BUGS
449: When comparing directories with the
450: .Fl b ,
451: .Fl w
452: or
453: .Fl i
454: options specified,
1.5 jmc 455: .Nm
1.1 deraadt 456: first compares the files ala
1.5 jmc 457: .Xr cmp 1 ,
1.1 deraadt 458: and then decides to run the
1.5 jmc 459: .Nm
1.1 deraadt 460: algorithm if they are not equal.
461: This may cause a small amount of spurious output if the files
462: then turn out to be identical because the only differences are
1.5 jmc 463: insignificant whitespace or case differences.