======Synopsis:======
[[on]] [<modes>]notify_signon [<serial#>] [-|^]<match> { <action> }

======Description:======
This hook is triggered whenever the client detects that a nickname on its
internal [[notify command|NOTIFY]] list has signed on to irc.

======Parameters:======
|$0 |nickname that signon was detected for                                                                              |
|$1 |user@host of person signing on (if [[set]](4) [[set notify_userhost_automatic|notify_userhost_automatic]] is ON)   |