To print the common elements in both files:
$ awk 'NR==FNR{a[$1];next}$1 in a{print $1}' file1 file2
"aba"
"abc"
"xxx"
Explanation:
NR
and FNR
are awk
variables that store the total number of records and the number of records in the current files respectively (the default record is a line).
NR==FNR # Only true when in the first file
{
a[$1] # Build associative array on the first column of the file
next # Skip all proceeding blocks and process next line
}
($1 in a) # Check in the value in column one of the second files is in the array
{
# If so print it
print $1
}
If you want to match the whole lines then use $0
:
$ awk 'NR==FNR{a[$0];next}$0 in a{print $0}' file1 file2
"aba" 0 0
"xxx" 0 0
Or a specific set of columns:
$ awk 'NR==FNR{a[$1,$2,$3];next}($1,$2,$3) in a{print $1,$2,$3}' file1 file2
"aba" 0 0
"xxx" 0 0