diff utility exclude option

[keydrive]

I need to exclude a line when using UNIX diff utility. I have 4 files, the first two f1 and f2 work with the command however does not on f3 and f4.

Suggestions?

This works

diff -I '^<committed.*' f1 f2

f1
<committed:123> </committed>
<committed_docu ments>4</committed_docum ents>

f2
<committed:345> </committed>
<committed_docu ments>46</committed_docum ents>



But these don't

diff -I '^<committed.*' f3 f4
diff -I '^\s<committed.*' f3 f4
diff -I '^[:punct:]committed.*' f3 f4

f3
<committed_docu ments>4</committed_docum ents>
<terms>880</terms>

f4
<committed_docu ments>46</committed_docum ents>
<terms>80</terms>

[Luuk]

diff -I '^<committed.' -I 'terms' f3 f4