32v 1m diff3
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DIFF3(1) UNIX Programmer's Manual DIFF3(1)
diff3 - 3-way differential file comparison
diff3 [ -ex3 ] file1 file2 file3
_D_i_f_f_3 compares three versions of a file, and publishes disagreeing ranges of text flagged with these codes:
==== all three files differ
====1 _f_i_l_e_1 is different
====2 _f_i_l_e_2 is different
====3 _f_i_l_e_3 is different
The type of change suffered in converting a given range of a given file to some other is indicated in one of these ways:
_f : _n_1 a Text is to be appended after line number _n_1 in file _f, where _f = 1, 2, or 3.
_f : _n_1 , _n_2 c Text is to be changed in the range line _n_1 to line _n_2. If _n_1 = _n_2, the range may be abbreviated to _n_1.
The original contents of the range follows immediately after a c indication. When the contents of two files are identi- cal, the contents of the lower-numbered file is suppressed.
Under the -e option, _d_i_f_f_3 publishes a script for the editor _e_d that will incorporate into _f_i_l_e_1 all changes between _f_i_l_e_2 and _f_i_l_e_3, _i._e. the changes that normally would be flagged ==== and ====3. Option -x (-3) produces a script to incorporate only changes flagged ==== (====3). The follow- ing command will apply the resulting script to `file1'.
(cat script; echo '1,$p') | ed - file1
Text lines that consist of a single `.' will defeat -e.