I just read source code of libdispatch, but i found there is a word, "voucher", just appear so many times, but i do not know what it is mean actually. So could any tell me the true means of this word, thank you very much for your great help.
Best Regards Axis
I just find answer from source code:
/*
* Mach Voucher - an immutable collection of attribute value handles.
*
* The mach voucher is such that it can be passed between processes
* as a Mach port send right (by convention in the mach_msg_header_t’s
* msgh_voucher field).
*
* You may construct a new mach voucher by passing a construction
* recipe to host_create_mach_voucher(). The construction recipe supports
* generic commands for copying, removing, and redeeming attribute value
* handles from previous vouchers, or running attribute-mananger-specific
* commands within the recipe.
*
* Once the set of attribute value handles is constructed and returned,
* that set will not change for the life of the voucher (just because the
* attribute value handle itself doesn't change, the value the handle refers
* to is free to change at will).
*/
Best Regards
Axis
