16.22 Comparing Two Directory Trees with dircmp

You have an original directory. You copy the files in it to another directory, edit some of them, and add a few others. Later, you want to know the differences between the two directories. If your system's diff ( 28.1 ) has a -r (recursive) option, you can use that. System V has dircmp . The output of dircmp is formatted with pr ( 43.7 ) ; you get 66-line-long pages with headings:

% 

dircmp a b

  Sep 16 09:26 1991  a only and b only Page 1  ./foo.tmp                                   ./defs.h    ...  Sep 16 09:26 1991  Comparison of a b Page 1  directory   . same        ./Makefile directory   ./data same        ./data/test1 same        ./data/test2    ...  different   ./pqp.help same        ./pqs.help    ...

In the a only and b only listing, files only in the first directory are in the first column and files only in the second directory are in the second column. The Comparison of a b listing compares files that are in both directories. The comparison is recursive - if there are any subdirectories, dircmp checks those, too.

The dircmp -s option stops the "identical file" messages. Use -d to run diff on files that are different; dircmp prints a new page for each diff it runs:

% 

dircmp -d -s a b

 Sep 16 09:35 1991  a only and b only Page 1    ... Sep 16 09:35 1991  Comparison of a b Page 1    ... Sep 16 09:35 1991  diff of ./pqp.help in a and b Page 1  3c3,4 < -#    "Only this printer"... 'pqp -3' would print on #3. -- > -#    "Only this printer"... 'pqp -3' would print only on #3; >       other printer queues will be held.    ...

The designers assumed you'd want to send the output to a printer. I usually read it on my screen with the less ( 25.4 ) pager and its -s option, which squeezes out the multiple blank lines. If you don't have less or more -s , try piping the output through cat -s ( 25.10 ) or a sed filter ( 34.18 ) .