Section 3 · Library functions

epoll_data_t.3type

Package: man-pages

epoll_event

epoll_event, epoll_data, epoll_data_t − epoll event

Standard C library (libc)

#include <sys/epoll.h>

struct epoll_event {
uint32_t events; /* Epoll events */ **
epoll_data_t data;** /* User data variable */ **
};**

union epoll_data {
void *ptr;
int fd;
uint32_t u32;
uint64_t u64;
};

typedef union epoll_data epoll_data_t;

The epoll_event structure specifies data that the kernel should save and return when the corresponding file descriptor becomes ready.

The Linux kernel headers also provide this type, with a slightly different definition:

#include <linux/eventpoll.h>
struct epoll_event {
__poll_t events;
__u64 data;
};

Linux.