diff options
Diffstat (limited to 'apps/uORB/uORB.h')
| -rw-r--r-- | apps/uORB/uORB.h | 21 |
1 files changed, 18 insertions, 3 deletions
diff --git a/apps/uORB/uORB.h b/apps/uORB/uORB.h index c36d0044f..eb068d2b7 100644 --- a/apps/uORB/uORB.h +++ b/apps/uORB/uORB.h @@ -106,11 +106,26 @@ struct orb_metadata { __BEGIN_DECLS /** + * ORB topic advertiser handle. + * + * Advertiser handles are global; once obtained they can be shared freely + * and do not need to be closed or released. + * + * This permits publication from interrupt context and other contexts where + * a file-descriptor-based handle would not otherwise be in scope for the + * publisher. + */ +typedef intptr_t orb_advert_t; + +/** * Advertise as the publisher of a topic. * * This performs the initial advertisement of a topic; it creates the topic * node in /obj if required and publishes the initial data. * + * Any number of advertisers may publish to a topic; publications are atomic + * but co-ordination between publishers is not provided by the ORB. + * * @param meta The uORB metadata (usually from the ORB_ID() macro) * for the topic. * @param data A pointer to the initial data to be published. @@ -122,7 +137,7 @@ __BEGIN_DECLS * ORB_DEFINE with no corresponding ORB_DECLARE) * this function will return -1 and set errno to ENOENT. */ -extern int orb_advertise(const struct orb_metadata *meta, const void *data) __EXPORT; +extern orb_advert_t orb_advertise(const struct orb_metadata *meta, const void *data) __EXPORT; /** * Publish new data to a topic. @@ -131,13 +146,13 @@ extern int orb_advertise(const struct orb_metadata *meta, const void *data) __EX * will be notified. Subscribers that are not waiting can check the topic * for updates using orb_check and/or orb_stat. * - * @handle The handle returned from orb_advertise. * @param meta The uORB metadata (usually from the ORB_ID() macro) * for the topic. + * @handle The handle returned from orb_advertise. * @param data A pointer to the data to be published. * @return OK on success, ERROR otherwise with errno set accordingly. */ -extern int orb_publish(const struct orb_metadata *meta, int handle, const void *data) __EXPORT; +extern int orb_publish(const struct orb_metadata *meta, orb_advert_t handle, const void *data) __EXPORT; /** * Subscribe to a topic. |