['] [userid] [/ [password]] [@net_service_name] [']

##</code><code>##

my ($userid, $password, $netServiceName) = /'?([^@\/']+)?(\/[^@\/']*)?(@[^@\/']+)?'?/;

##</code><code>##

>>SYS/change_on_install@prod1<<
<SYS> </change_on_install> <@prod1>
>>rman/rman@rcat<<
<rman> </rman> <@rcat>
>>SYS<<
<SYS> <> <>
>>/<<
<> </> <>
>>/fooey<<
<> </fooey> <>
>>/fooey@foobar<<
<> </fooey> <@foobar>
>>SYS@foobar<<
<SYS> <> <@foobar>
>>'simple/fooey@foobar'<<
<simple> </fooey> <@foobar>