ioctl_pipe(2) System Calls Manual ioctl_pipe(2)
NAME
ioctl_pipe - ioctl() operations for General notification mechanism
SYNOPSIS
#include <linux/watch_queue.h> /* Definition of IOC_WATCH_QUEUE_* */
#include <sys/ioctl.h>
int ioctl(int pipefd[1], IOC_WATCH_QUEUE_SET_SIZE, int size);
int ioctl(int pipefd[1], IOC_WATCH_QUEUE_SET_FILTER,
struct watch_notification_filter *filter);
DESCRIPTION
The following ioctl(2) operations are provided to set up general notifi-
cation queue parameters. The notification queue is built on the top of
a pipe(2) opened with the O_NOTIFICATION_PIPE flag.
IOC_WATCH_QUEUE_SET_SIZE (since Linux 5.8)
Preallocates the pipe buffer memory so that it can fit size noti-
fication messages. Currently, size must be between 1 and 512.
IOC_WATCH_QUEUE_SET_FILTER (since Linux 5.8)
Watch queue filter can limit events that are received. Filters
are passed in a struct watch_notification_filter and each filter
is described by a struct watch_notification_type_filter struc-
ture.
struct watch_notification_filter {
__u32 nr_filters;
__u32 __reserved;
struct watch_notification_type_filter filters[];
};
struct watch_notification_type_filter {
__u32 type;
__u32 info_filter;
__u32 info_mask;
__u32 subtype_filter[8];
};
SEE ALSO
pipe(2), ioctl(2)
Linux man-pages 6.9.1 2024-05-02 ioctl_pipe(2)
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