Visit The New, Modern Unix Linux Community

Linux and UNIX Man Pages

Test Your Knowledge in Computers #706
Difficulty: Medium
Shared information bias is known as the tendency for group members to spend more time and energy discussing information that all members are already familiar with (i.e., shared information), and less time and energy discussing information that only some members are aware of.
True or False?
Linux & Unix Commands - Search Man Pages

diff(1) [v7 man page]

DIFF(1) 						      General Commands Manual							   DIFF(1)

NAME
diff - differential file comparator SYNOPSIS
diff [ -efbh ] file1 file2 DESCRIPTION
Diff tells what lines must be changed in two files to bring them into agreement. If file1 (file2) is `-', the standard input is used. If file1 (file2) is a directory, then a file in that directory whose file-name is the same as the file-name of file2 (file1) is used. The normal output contains lines of these forms: n1 a n3,n4 n1,n2 d n3 n1,n2 c n3,n4 These lines resemble ed commands to convert file1 into file2. The numbers after the letters pertain to file2. In fact, by exchanging `a' for `d' and reading backward one may ascertain equally how to convert file2 into file1. As in ed, identical pairs where n1 = n2 or n3 = n4 are abbreviated as a single number. 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 `>'. The -b option causes trailing blanks (spaces and tabs) to be ignored and other strings of blanks to compare equal. The -e option produces a script of a, c and d commands for the editor ed, which will recreate file2 from file1. The -f option produces a similar script, not useful with ed, in the opposite order. In connection with -e, the following shell program may help maintain multiple versions of a file. Only an ancestral file ($1) and a chain of version-to-version ed scripts ($2,$3,...) made by diff need be on hand. A `latest version' appears on the standard output. (shift; cat $*; echo '1,$p') | ed - $1 Except in rare circumstances, diff finds a smallest sufficient set of file differences. Option -h does a fast, half-hearted job. It works only when changed stretches are short and well separated, but does work on files of unlimited length. Options -e and -f are unavailable with -h. FILES
/tmp/d????? /usr/lib/diffh for -h SEE ALSO
cmp(1), comm(1), ed(1) DIAGNOSTICS
Exit status is 0 for no differences, 1 for some, 2 for trouble. BUGS
Editing scripts produced under the -e or -f option are naive about creating lines consisting of a single `.'. DIFF(1)

Check Out this Related Man Page

diff3(1)						      General Commands Manual							  diff3(1)

Name
       diff3 - 3-way differential file comparison

Syntax
       diff3 [-ex3] file1 file2 file3

Description
       The command compares three versions of a file, and publishes the ranges of text that disagree, flagged with the following codes:

	  ====	      all three files differ

	  ====1       file1 is different

	  ====2       file2 is different

	  ====3       file3 is different

       The type of change needed to convert a given range of a given file to some other is indicated in one of these ways:

	  f : n1 a    Text is to be appended after line number n1 in file f, where f = 1, 2, or 3.

	  f : n1 , n2 c
		      Text is to be changed in the range line n1 to line n2.  If n1 = n2, the range may be abbreviated to n1.

       The original contents of the range follows immediately after a c indication.  When the contents of two files are identical, the contents of
       the lower-numbered file is suppressed.

Options
       -3   Produces an editor script containing the changes between file1 and file2 that are to be incorporated into file3.

       -e	   Produces an editor script containing the changes between file2 and file3 that are to be incorporated into file1.

       -x	   Produces an editor script containing the changes among all three files.

Examples
       Under the -e option, publishes a script for the editor that incorporates into file1 all changes between file2 and  file3  -  that  is,  the
       changes	that would normally be flagged ==== and ====3.	Option -x (-3) produces a script to incorporate only changes flagged ==== (====3).
       The following command applies the resulting script to `file1':
       (cat script; echo '1,$p') | ed - file1

Restrictions
       Text lines that consist of a single `.'	defeat -e.

Files
       /tmp/d3?????
       /usr/lib/diff3

See Also
       cmp(1), comm(1), diff(1), dffmk(1), join(1), sccsdiff(1), uniq(1)

																	  diff3(1)

Featured Tech Videos