Searching Text Files for Large Numbers
 

Hi Linux Gurus,

I am looking for a way to search for large numbers in text files and print the nearby lines.

For example if I had a text file like:

Event: 11
blah: 3
blah: 41 bleh: 19
Event: 2
blah: 31
blah: 4 bleh: 91
Event: 3
blah: 3
blah: 4 bleh: 9

I want to pick out lines with numbers above 50 and the previous 2 lines. In this case I would want to pick out:

Event: 2
blah: 31
blah: 4 bleh: 91

This doesn't seem like it should be hard, but I am sure having a hard time figuring out a way. Any help would be greatly appreciated.

Thanks in advance,
Will

use egrep, which is grep, but searching for regular expressions. to form a regular expression read man regex. Off the yop of my head, you're looking for something like

egrep -C5 -e 'nnn' <file to search> |less

You can also steer it to use the Perl regex rules (better organised than Posix) and covered by man perlre. Bury your head for a day.