Our system administrator has set up a [MySQL] database for us.  I can connect to it through the ssh terminal window or telnet, using the following command, as suggested by him:
       mysql -h localhost --socket=/tmp/mysql.sock2 -u myname -p
followed by ENTER, and then my password. Then I can "use" my database, run SQL commands, create a table, insert a record etc.

However I have been unable to connect to it in PHP.

I have tried this code
       $dbh = mysql_connect("localhost", "myname", "xxxxxxxx") or die ("Cannot connect to db");
(where the x's are my password) and this which was suggested by the administrator:
       $link = @mysql_connect("localhost", "myname", "xxxxxxxx") or exit();
With or without the @, it does not work.

Have you got any suggestions?

Your PHP code doesn't make any reference to the socket, so it's assuming the default MySQL socket.  All that adding the "@" character does is tell PHP to ignore any errors in the function.

Try:
dbh = mysql_connect("localhost:/tmp/mysql.sock2", "myname", "xxxxxxxx")

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