ticket.sys is a file that contains the ticket for each app installed on the console.
In the code there appears to be a hard limit of 48 tickets in ticket.sys. There may be further practical limits on the number of tickets in ticket.sys (and therefore also on the number of titles installed on a console).
|0x0||0x04||numTickets||Number of tickets contained in the file|
|0x04||(variable)||Tickets||Array of tickets|