Shell Programming and Scripting

while read name
do
grep -owP "(?:\w+\s){0,2}$name(?:\s\w+){0,2}" big_file.txt
done < words_file.txt

dump=$(<big_file.txt)
while read name
do
echo $dump | grep -owP "(?:\w+\s){0,2}$name(?:\s\w+){0,2}"
done < words_file.txt

in 2004 obama received national attention during his campaign to represent 
illinois in the united states senate with his victory in the march democratic 
party primary his keynote address at the democratic national convention in july 
and his election to the senate in november he began his presidential campaign
in 2007 and after a close primary campaign against hillary rodham clinton 
in 2008 he won sufficient delegates in the democratic party primaries to receive 
the presidential nomination he then defeated republican nominee john mccain 
in the general election and was inaugurated as president on january 20 2009
nine months after his inauguration obama was named the 2009 nobel peace prize laureate

obama
primaries
water
laureate
computer

in 2004 obama received national
his inauguration obama was named
democratic party primaries to receive
peace prize laureate

grep -C2 -fwords_file <(tr ' ' '\n' < big_file)
in
2004
obama
received
national
--
democratic
party
primaries
to
receive
--
his
inauguration
obama
was
named
--
peace
prize
laureate

grep -w 'obama\|primaries\|water' big_file.txt

grep -owP "(?:\w+\s){0,2}obama\|primaries\|water(?:\s\w+){0,2}" big_file.txt

grep -owP "(\w+\s){0,2}(obama|primaries|water)(\s\w+){0,2}" <your_input_file>

in 2004 obama received national
democratic party primaries to receive
his inauguration obama was named

LC_ALL=C grep -owP "(\w+\s){0,2}(obama|primaries|water)(\s\w+){0,2}" big_file.txt

parallel --pipepart --block 100M -a big_file.txt --fifo cat words_file.txt | parallel --pipe -L1000 --round-robin grep -f - {}

parallel --pipepart --block 100M -a big_file.txt --fifo cat  words_file.txt | parallel --pipe -L1000 --round-robin grep -fowP "(?:\w+\s){0,2}$name(?:\s\w+){0,2}" -  {}