UNIX for Dummies Questions & Answers

grep -F -f List.csv Data.csv > Output.csv

aa
bb
cc
dd

aa,other stuff
zz,other stuff
bb,other stuff
aa_2,other stuff
dd,other stuff
dd_2,other stuff

aa,other stuff
bb,other stuff
aa_2,other stuff
dd,other stuff
dd_2,other stuff

sed 's/.*/^&,/' file1 | grep -f- file2

awk 'NR==FNR{A[$1]; next} $1 in A' file1 FS=, file2

awk 'NR==FNR{A[$1]; next} $1 in A' file1 FS=, file2

awk: NR==FNR{A[]; next}  in A
awk:           ^ syntax error
awk: fatal: invalid subscript expression

qw("awk 'NR==FNR{A[$1]; next} $10 in A' $filePortfolios FS=, $fileIn > $fileTemp");