The file .pgpass in a user's home directory or the
file referenced by PGPASSFILE can contain passwords to
be used if the connection requires a password (and no password has been
specified otherwise). On Microsoft Windows the file is named
%APPDATA%\postgresql\pgpass.conf (where
%APPDATA% refers to the Application Data subdirectory in
the user's profile).
This file should contain lines of the following format:
hostname:port:database:username:password
Each of the first four fields may be a literal value, or *,
which matches anything. The password field from the first line that matches the
current connection parameters will be used. (Therefore, put more-specific
entries first when you are using wildcards.)
If an entry needs to contain : or
\, escape this character with \.
A host name of localhost matches both TCP (hostname
localhost) and Unix domain socket (pghost empty or the
default socket directory) connections coming from the local machine.
The permissions on .pgpass must disallow any
access to world or group; achieve this by the command
chmod 0600 ~/.pgpass.
If the permissions are less strict than this, the file will be ignored.
(The file permissions are not currently checked on Microsoft Windows,
however.)