Yes...

Karls-Mac-mini:Desktop karl$ grep -C1 4003 MyData.txt 
4002_1#2
4003_1#3
4004_1#4

[download]

...but do you really want to qx this on a 4 GByte file? Regards, Karl

«The Crux of the Biscuit is the Apostrophe»

In reply to Re^2: How to print the lines immediately above and below a matching line? by karlgoethebier
in thread How to print the lines immediately above and below a matching line? by Bio90

Title:
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