Hey guys,
I've got a scripting problem that has been bugging me so thought I'd ask the wise people here! Basically I have two overlapping log files, and I want to get the newest lines from the new log file that aren't in the old log file - but not the old lines in the old log that aren't in the new log.
Say the old log file has this content:
1: Apple
2: Banana
3: Carrot
4: Dog
And the new log has this content:
3: Carrot
4: Dog
5: Elephant
6: Fish
I want my script to output:
5: Elephant
6: Fish
Essentially, I want a diff of the two files, but only include the lines that are unique to the second file - is this possible?
edit: It seems that I can do it with "grep -v -x -f file1 file2", but this has O(n^2) complexity so won't work nearly fast enough with files that are reasonably long. Any other ideas?
Thanks for any help!
Giancarlo