udev_device_has_tag

Index · Directives systemd 234

## Name

udev_device_has_tag, udev_device_get_devlinks_list_entry, udev_device_get_properties_list_entry, udev_device_get_tags_list_entry, udev_device_get_sysattr_list_entry, udev_device_get_property_value, udev_device_get_sysattr_value, udev_device_set_sysattr_value — Retrieve or set device attributes

## Synopsis

    #include <libudev.h>

`struct udev_list_entry *udev_device_get_devlinks_list_entry(` | struct udev_device *udev_device`)`;

`struct udev_list_entry *udev_device_get_properties_list_entry(` | struct udev_device *udev_device`)`;

`struct udev_list_entry *udev_device_get_tags_list_entry(` | struct udev_device *udev_device`)`;

`struct udev_list_entry *udev_device_get_sysattr_list_entry(` | struct udev_device *udev_device`)`;

`const char *udev_device_get_property_value(` | struct udev_device *udev_device,
| const char *key`)`;

`int udev_device_has_tag(` | struct udev_device *udev_device,
| const char *tag`)`;

`const char *udev_device_get_sysattr_value(` | struct udev_device *udev_device,
| const char *sysattr`)`;

`int udev_device_set_sysattr_value(` | struct udev_device *udev_device,
| const char *sysattr,
| const char *value`)`;

## Return Value

On success, `udev_device_get_devlinks_list_entry()`, `udev_device_get_properties_list_entry()`, `udev_device_get_tags_list_entry()` and `udev_device_get_sysattr_list_entry()` return a pointer to the first entry of the retrieved list. If that list is empty, or if an error occurred, `NULL` is returned.

On success, `udev_device_get_property_value()` and `udev_device_get_sysattr_value()` return a pointer to a constant string of the requested value. On error, `NULL` is returned.

On success, `udev_device_set_sysattr_value()` returns an integer greater than, or equal to, `0`. On failure, a negative error code is returned.

On success, `udev_device_has_tag()` returns `1` or `0`, depending on whether the device has the given tag or not. On failure, a negative error code is returned.

## See Also

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