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test.txt is a file that contains:
target1 A A A A B B B
target2 B B B B B B B
target3 D F F F F F F
target4 F F F F F F F
target5 G G G G G G G
How can I do the same thing but instead of using egrep 'target1|target2|target3|target4|etc' use a file that contains a list with all the 1000 targets I'm interested on. Something like:
while read pattern; do grep $pattern file; done < patterns
some issues with this, (assuming the samples as it is provided)
1)probably should put a boundary on the grep pattern, eg grep "target1" will also match target10 or target100 ....which will give ambiguous results
2)assuming "patterns" file has 1000 targets as OP has mentioned, so the code will call grep 1000 times on "file". it would be slower than going through the file once( as in the awk example). Its even slower if "file" is a big file.