Perform a Generic Attribute (GATT) call to write a value from a provided handle.
Synopsis:
#include <btapi/btgatt.h>
int bt_gatt_write_value(int instance, uint16_t handle, uint16_t offset, const uint8_t *data, int size)
Arguments:
- instance
-
The identifier used to reference the connected primary service.
- handle
-
The to the value to be written.
- offset
-
The offset to begin writing from.
- data
-
An array of data to be written.
- size
-
The size of the array to be written.
Library:
libbtapi (For the qcc command, use the -l btapi option to link against this library)
Description:
This function writes values and expects a response from the remote Bluetooth-enabled device. The size of the value to be written cannot be larger than ATT_MTU - 3 bytes.
Returns:
EOK when data writing is successfully completed,
-1 with the
errno set otherwise. The error codes that can be returned are as follows:
- E2BIG: The requested write size is larger than ATT_MTU - 3 bytes.
- EACCESS: Insufficient authentication or authorization.
- EBUSY: The stack was busy performing another operation. You can try again later.
- EDEADLK: A potential deadlock has been avoided.
- EINVAL: The arguments passed are invalid or the connection to the remote Bluetooth-enabled device is unavailable.
- ENODEV: Unable to find the service connection defined by the instance argument.
- ENOENT: An invalid handle was provided for the GATT server.
- ENOMEM: Insufficient memory to perform the request.
- ENOSYS: The operation failed at the stack level.
- ENXIO: An unknown handle value was provided for a service.
- EPERM: An attribute could not be written to.
- EPROTO: The operation failed because the response from the remote Bluetooth-enabled device had a protocol error.
- ESRCH: The service connection was not available.
- ESRVRFAULT: An internal error has occurred.