Shell Programming and Scripting

awk 'NR==FNR{
A[$1,$2]=$0; next}
{
if(A[$1,$2])
print A[$1,$2]?$0 FS "available" : $0 FS "not available"
}' FS="\t" reference.txt file1.txt

awk 'NR==FNR{A[$0]=$0; next}{print A[$0]?A[$0] FS "available" : $0 FS "not available";delete A[$0] }
    END{for (i in A){if(A[i]){print A[i],"unmatched reference file"}}}' reference.txt file1.txt

awk 'NR==FNR{A[$0]=$0; next}    # Here we read reference.txt file and store it in array A with index as $0.

{print A[$0]?A[$0] FS "available" : $0 FS "not available";    # Here we check $0 is available or not in Array A. If $0 is present then print as available or not available.

delete A[$0] }    # Here for those who are availabe delete those records from Array.

END{for (i in A){if(A[i]){print A[i],"unmatched reference file"}}}'    # Here print those records which is not present in file1.txt