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| author | bhgv <bhgv.empire@gmail.com> | 2018-03-01 16:54:45 +0200 |
|---|---|---|
| committer | bhgv <bhgv.empire@gmail.com> | 2018-03-01 16:54:45 +0200 |
| commit | b786f20bbab5a59046aa78a2c6c2a11536497202 (patch) | |
| tree | 0851ecdec889eb9b7ba3751cc04d4f0b474e4a9e /man/1/diff | |
inferno-os tree was separated from the inferno-os-android (separated from the Android driver)
Diffstat (limited to 'man/1/diff')
| -rw-r--r-- | man/1/diff | 136 |
1 files changed, 136 insertions, 0 deletions
diff --git a/man/1/diff b/man/1/diff new file mode 100644 index 0000000..494dacf --- /dev/null +++ b/man/1/diff @@ -0,0 +1,136 @@ +.TH DIFF 1 +.SH NAME +diff \- differential file comparator +.SH SYNOPSIS +.B diff +[ +.B -efbwr +] file1 ... file2 +.SH DESCRIPTION +.I Diff +tells what lines must be changed in two files to bring them +into agreement. +If one file +is a directory, +then a file in that directory with basename the same as that of +the other file is used. +If both files are directories, similarly named files in the +two directories are compared by the method of +.I diff +for text +files and +.IR cmp (1) +otherwise. +If more than two file names are given, then each argument is compared +to the last argument as above. +The +.B -r +option causes +.I diff +to process similarly named subdirectories recursively. +The normal output contains lines of these forms: +.IP "" 5 +.I n1 +.B a +.I n3,n4 +.br +.I n1,n2 +.B d +.I n3 +.br +.I n1,n2 +.B c +.I n3,n4 +.PP +These lines resemble Plan 9 or Unix +.I ed +commands to convert +.I file1 +into +.IR file2 . +The numbers after the letters pertain to +.IR file2 . +In fact, by exchanging `a' for `d' and reading backward +one may ascertain equally how to convert +.I file2 +into +.IR file1 . +As in +.IR ed , +identical pairs where +.I n1 += +.I n2 +or +.I n3 += +.I n4 +are abbreviated as a single number. +.PP +Following each of these lines come all the lines that are +affected in the first file flagged by `<', +then all the lines that are affected in the second file +flagged by `>'. +.PP +The +.B -b +option causes +trailing blanks (spaces and tabs) to be ignored +and other strings of blanks to compare equal. +The +.B -w +option causes all white-space to be removed from input lines +before applying the difference algorithm. +.PP +The +.B -e +option produces a script of +.I "a, c" +and +.I d +commands for the Plan 9 or Unix editor +.IR ed , +which will recreate +.I file2 +from +.IR file1 . +The +.B -f +option produces a similar script, +not useful with +.IR ed , +in the opposite order. It may, however, be +useful as input to a stream-oriented post-processor. +.PP +Except in rare circumstances, +.I diff +finds a smallest sufficient set of file +differences. +.SH FILES +.B /tmp/diff[12] +.SH SOURCE +.B /appl/cmd/diff.b +.SH DIAGNOSTICS +Exit status is the empty string +for no differences, +.L some +for some, +and +.L error +for trouble. +.SH "SEE ALSO" +.IR cmp (1) +.SH BUGS +Editing scripts produced under the +.BR -e " or" +.BR -f " option are naive about" +creating lines consisting of a single `\fB.\fR'. +.br +When running +.I diff +on directories, the notion of what is a text +file is open to debate. +.br +Nothing directly interprets the +.I ed +scripts within the Inferno environment. |
