linha de comando:
diff --exclude=direxclude -r dir1 dir2
openSUSE 12.1: ok.
sttr@linux-sgfb:/tmp> md dir1
sttr@linux-sgfb:/tmp> md dir2
sttr@linux-sgfb:/tmp> cd dir2
sttr@linux-sgfb:/tmp/dir2> md 10
sttr@linux-sgfb:/tmp/dir2> md 11
sttr@linux-sgfb:/tmp/dir2> md 12
sttr@linux-sgfb:/tmp/dir2> md 14
sttr@linux-sgfb:/tmp/dir2> cd ..
sttr@linux-sgfb:/tmp> cd dir1
sttr@linux-sgfb:/tmp/dir1> md 15
sttr@linux-sgfb:/tmp/dir1> md 11
sttr@linux-sgfb:/tmp/dir1> md 12
sttr@linux-sgfb:/tmp/dir1> md 17
sttr@linux-sgfb:/tmp/dir1> cd ..
sttr@linux-sgfb:/tmp> diff --exclude="11" -r dir1 dir2
Only in dir2: 10
Only in dir2: 14
Only in dir1: 15
Only in dir1: 17
sttr@linux-sgfb:/tmp> diff --exclude=11 -r dir1 dir2
Only in dir2: 10
Only in dir2: 14
Only in dir1: 15
Only in dir1: 17
sttr@linux-sgfb:/tmp>
CentOS 6.3 64: ok.
[root@local tmp]# mkdir dir1
....
Ubuntu 12.04 TLS: ok.