PostgreSQLpgagent "Running at: is not runing"
since you're specifying 

pgagent hostaddr=127.0.0.1 dbname=mydb user=postgres

change .pgpass to match it

127.0.0.1:5432:*:postgres:mypass

or specify 

*:5432:*:postgres:mypass

Edit: And change the permissions of .pgpass back to 0600 else you'll get the message:

WARNING: password file "~/.pgpass" has group or world access; permissions should be u=rw (0600) or less

and for command line, it prompts for password