Thread: cygwin: create function getpid (backend process id) - equivalent to MS SQL Server SPID ?

Could anyone confirm that the returned value from the function below behaves the same way as MS SQL Server @@SPID variable and that it remains unchanged and unique throughout a connection ?
 
    create function getpid() returns int as '/bin/cygwin1.dll' language 'c';
    select getpid();
 
Thanx a lot.
 
    Cédric Dufour