How to get variable out to shell script

I am using psql to call an external sql file that executes a simple select count(*):

ie: select into ct count(*) from table;

I can't figure out how to make the ct variable available to the shell script once the external sql file completes execution.  What I am trying to do is run the count command against a table in two different databases on two different servers and then compare the variables.

Any ideas?

Thanks in advance.

Alex