I expect so \c without parameters has only informational character. But \c reset user.
postgres=# set role to tom; SET Time: 0.787 ms postgres=> select current_user; +--------------+ | current_user | +--------------+ | tom | +--------------+ (1 row)
Time: 0.851 ms postgres=> \c You are now connected to database "postgres" as user "pavel". postgres=# select current_user; +--------------+ | current_user | +--------------+ | pavel | +--------------+ (1 row)
