NAME¶
io_getcookie - retrieve cookie
SYNTAX¶
#include <io.h>
void*
io_getcookie(int64 fd);
DESCRIPTION¶
io_getcookie retrieves a cookie (pointer to some anonymous data structure you
associated with this descriptor).
Use
io_setcookie(3) to associate a cookie with a descriptor.
If you did not associate a cookie with this descriptor, io_getcookie returns
NULL.
The idea is that you put the state associated with a TCP connection you serve in
a common struct. Then you do not need to have your own data structure to
retrieve the state for a connection, you can just use the data structure
io_wait already maintains. The lookup works in constant time and should not
cause any cache misses.
SEE ALSO¶
io_wait(3),
io_setcookie(3)