Index · Directives systemd 250


udev_device_get_syspath, udev_device_get_sysname, udev_device_get_sysnum, udev_device_get_devpath, udev_device_get_devnode, udev_device_get_devnum, udev_device_get_devtype, udev_device_get_subsystem, udev_device_get_driver, udev_device_get_udev, udev_device_get_parent, udev_device_get_parent_with_subsystem_devtype, udev_device_get_is_initialized, udev_device_get_action — Query device properties


#include <libudev.h>
const char *udev_device_get_syspath(struct udev_device *udev_device);
const char *udev_device_get_sysname(struct udev_device *udev_device);
const char *udev_device_get_sysnum(struct udev_device *udev_device);
const char *udev_device_get_devpath(struct udev_device *udev_device);
const char *udev_device_get_devnode(struct udev_device *udev_device);
dev_t udev_device_get_devnum(struct udev_device *udev_device);
const char *udev_device_get_devtype(struct udev_device *udev_device);
const char *udev_device_get_subsystem(struct udev_device *udev_device);
const char *udev_device_get_driver(struct udev_device *udev_device);
struct udev *udev_device_get_udev(struct udev_device *udev_device);
struct udev_device *udev_device_get_parent(struct udev_device *udev_device);
struct udev_device *udev_device_get_parent_with_subsystem_devtype(struct udev_device *udev_device,
 const char *subsystem,
 const char *devtype);
int udev_device_get_is_initialized(struct udev_device *udev_device);
const char *udev_device_get_action(struct udev_device *udev_device);

Return Value

On success, udev_device_get_syspath(), udev_device_get_sysname(), udev_device_get_sysnum(), udev_device_get_devpath(), udev_device_get_devnode(), udev_device_get_devtype(), udev_device_get_subsystem(), udev_device_get_driver() and udev_device_get_action() return a pointer to a constant string that describes the requested property. The lifetime of this string is bound to the device it was requested on. On failure, each function may return NULL.

On success, udev_device_get_devnum() returns the device type of the passed device. On failure, a device type with minor and major number set to 0 is returned.

udev_device_get_udev() always returns a valid pointer to the udev context that this device belongs to.

On success, udev_device_get_parent() and udev_device_get_parent_with_subsystem_devtype() return a pointer to the parent device. No additional reference to this device is acquired, but the child device owns a reference to such a parent device. On failure, NULL is returned.

On success, udev_device_get_is_initialized() returns either 1 or 0, depending on whether the passed device has already been initialized by udev or not. On failure, a negative error code is returned. Note that devices for which no udev rules are defined are never reported initialized.

See Also

udev_new(3), udev_device_new_from_syspath(3), udev_device_has_tag(3), udev_enumerate_new(3), udev_monitor_new_from_netlink(3), udev_list_entry(3), systemd(1)