efficient way to find diff

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# 1  
Old 07-08-2011
efficient way to find diff

I have two files A and B. I want to create file C which is A - B. I am currently using

grep -v -f B A > C

Is there a more efficient way. Files A and B are both large files


Last edited by radoulov; 07-08-2011 at 02:12 PM.. Reason: Code tags.
# 2  
Old 07-08-2011
if file B contains fixed strings (as opposed to regular expressions), you should add the -F option (or use fgrep, if the mentioned option is not available).
# 3  
Old 07-08-2011
File B does contain regular exprs
# 4  
Old 07-08-2011
I would use the same command.
Eventually you may get errors (not enough memory) if the files get bigger.
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