20.9. Peer Authentication
The peer authentication method works by obtaining the client's operating system user name from the kernel and using it as the allowed database user name (with optional user name mapping). This method is only supported on local connections.
The following configuration options are supported for peer :
- 
    
     map
- 
    Allows for mapping between system and database user names. See Section 20.2 for details. 
  Peer authentication is only available on operating systems providing
    the
  
   getpeereid()
  
  function, the
  
   SO_PEERCRED
  
  socket parameter, or similar mechanisms.  Currently that includes
  
   Linux
  
  ,
    most flavors of
  
   BSD
  
  including
  
   macOS
  
  ,
    and
  
   Solaris
  
  .