Some of the SNPs in my dataset are without rs ids, so in the bim file, they have dots instead of rs ids for them. So for errorless analysis how should replace the rs id column with that of the chromosome: location column instead?
This can also be done with plink 2.0's [--set-all-var-ids flag](https://www.cog-genomics.org/plink/2.0/data#set_all_var_ids).  

But it's more valuable to understand the **awk** solution, since that opens the door to a broadly useful set of text-manipulation techniques.

