appreciate any help with this task:
File A has 4 fields and has 90K lines. The first field (column 1) has a value that needs to be changed if criteria below met. The fourth field (column 4) has the data referenced in File B. The data in File A are tab separated DNS records:
Owner IN Type RData
hostname1 IN A 10.10.20.1 hostname2 IN A 10.10.20.2 hostname3 IN A 10.10.20.3
10.10.20.1 10.10.20.2 10.10.20.58 10.10.21.245 10.10.23.7
File B is single column (one field) and 1400 lines. The data in File B are IP addresses.
Requirement: For every line in File B, replace the contents of the the first field in File A if the fourth field in File A matches.
In English: For every IP that's listed in File B, replace the Owner value in File A with a specific value.