UDEV_MONITOR(3) BSD Library Functions Manual UDEV_MONITOR(3)NAME
udev_monitor_new, udev_monitor_ref, udev_monitor_unref,
udev_monitor_get_udev, udev_monitor_get_fd, udev_monitor_receive_device,
udev_monitor_enable_receiving,
udev_monitor_filter_add_match_subsystem_devtype,
udev_monitor_filter_add_match_expr,
udev_monitor_filter_add_match_property,
udev_monitor_filter_add_nomatch_expr,
udev_monitor_filter_add_nomatch_property,
udev_monitor_filter_add_match_regex,
udev_monitor_filter_add_nomatch_regex — device event monitor functions
LIBRARY
library “libdevattr”
SYNOPSIS
#include <devattr.h>
struct udev_monitor *
udev_monitor_new(struct udev *udev_ctx);
struct udev_monitor *
udev_monitor_ref(struct udev_monitor *udev_monitor);
void
udev_monitor_unref(struct udev_monitor *udev_monitor);
struct udev *
udev_monitor_get_udev(struct udev_monitor *udev_monitor);
int
udev_monitor_get_fd(struct udev_monitor *udev_monitor);
struct udev_device *
udev_monitor_receive_device(struct udev_monitor *udev_monitor);
int
udev_monitor_enable_receiving(struct udev_monitor *udev_monitor);
int
udev_monitor_filter_add_match_subsystem_devtype(struct udev_monitor *udev_monitor,
const char *subsystem, const char *devtype);
int
udev_monitor_filter_add_match_expr(struct udev_monitor *udev_monitor,
const char *key, char *expr);
int
udev_monitor_filter_add_match_property(struct udev_monitor *udev_monitor,
const char *key, const char *expr);
int
udev_monitor_filter_add_nomatch_expr(struct udev_monitor *udev_monitor,
const char *key, char *expr);
int
udev_monitor_filter_add_nomatch_property(struct udev_monitor *udev_monitor,
const char *key, const char *expr);
int
udev_monitor_filter_add_match_regex(struct udev_monitor *udev_monitor,
const char *key, char *expr);
int
udev_monitor_filter_add_nomatch_regex(struct udev_monitor *udev_monitor,
const char *key, char *expr);
DESCRIPTION
The udev_monitor_new() function creates a new udev_monitor object in the
specified udev context udev_ctx. It returns NULL if no such object could
be created.
The udev_monitor_ref() and udev_monitor_unref() functions increase or
decrease the reference count on a udev_monitor object respectively. When
the reference count drops to 0, the object is automatically destroyed and
any remaining event socket closed. The udev_monitor_ref() function
returns the same object that was passed in.
The udev_monitor_get_udev() function returns the udev context in which
the udev_monitor object was created.
The udev_monitor_enable_receiving() function enables receiving event
notifications matching the filters added by previous calls to
udev_monitor_filter_*(). The function returns -1 if an error occurs.
The udev_monitor_receive_device() function reads a udev_device, once the
monitor has been enabled for receiving. This call will block until a
device is available. It returns NULL if a read error occurs.
The udev_monitor_get_fd() returns the raw file descriptor on which events
are notified after a call to udev_monitor_enable_receiving(). This file
descriptor can then be used in conjunction with poll(2) or kqueue(2).
The udev_monitor_receive_device() call must be used to read from the
descriptor. The function returns -1 if the socket is not connected.
The udev_monitor_filter_add_match_subsystem_devtype() function adds a
filter that matches the given subsystem and/or devtype. If subsystem or
devtype is NULL, that argument is ignored. The function returns 0 in
case of success and a negative value if an error occurred. NOTE: Cur‐
rently devtype matching is not implemented.
The udev_monitor_filter_add_match_expr(),
udev_monitor_filter_add_match_property(),
udev_monitor_filter_add_nomatch_expr() and
udev_monitor_filter_add_nomatch_property() functions add a filter to
match or not to match, respectively, devices with the specified key and
value expr. The expr can contain wildcards. On error, these functions
return a negative value and 0 if no error occurred.
The udev_monitor_filter_add_match_regex(), and
udev_monitor_filter_add_nomatch_regex() functions add a filter to match
or not to match, respectively, devices with the specified key and value
expr. The expr can contain regular expressions according to regex(3).
On error, these functions return a negative value and 0 if no error
occurred.
SEE ALSOdevattr(3), udev(3), udev_device(3), udev_enumerate(3), udevd(8)BSD November 16, 2010 BSD
