Where can I find a list of Apple iOS errors for Core Bluetooth?

Question

I'm testing longevity/robustness issues now and need to debug occasional core Bluetooth errors, like #242.

Is there a list from Apple of what each core Bluetooth error means?

Answer 1

Normally, CoreBluetooth uses the standard error codes as defined in Bluetooth Core Spec V4.0 Vol 3 Part F Sec 3.4.1.1 Table 3.3 Error Codes.

                             Error 
Name                         Code  Description
==============================================================================
Invalid Handle               0x01  The attribute handle given was not valid on 
                                   this server.
Read Not Permitted           0x02  The attribute cannot be read.
Write Not Permitted          0x03  The attribute cannot be written.
Invalid PDU                  0x04  The attribute PDU was invalid.
Insufficient Authentication  0x05  The attribute requires authentication 
                                   before it can be read or written.
Request Not Supported        0x06  Attribute server does not support the 
                                   request received from the client.
Invalid Offset               0x07  Offset specified was past the end of the 
                                   attribute.
Insufficient Authorization   0x08  The attribute requires authorization before 
                                   it can be read or written.
Prepare Queue Full           0x09  Too many prepare writes have been queued.
Attribute Not Found          0x0A  No attribute found within the given 
                                   attribute handle range.
Attribute Not Long           0x0B  The attribute cannot be read or written 
                                   using the Read Blob Request
Insufficient Encryption Key  0x0C  The Encryption Key Size used for encrypting
Size                               this link is insufficient.
Invalid Attribute Value      0x0D  The attribute value length is invalid for 
Length                             the operation.
Unlikely Error               0x0E  The attribute request that was requested 
                                   has encountered an error that was unlikely, 
                                   and therefore could not be completed as 
                                   requested. 
Insufficient Encryption      0x0F  The attribute requires encryption before it 
                                   can be read or written.
Unsupported Group Type       0x10  The attribute type is not a supported 
                                   grouping attribute as defined by a higher 
                                   layer specification.
Insufficient Resources       0x11  Insufficient Resources to complete the 
                                   request
Reserved             0x012 – 0x7F  Reserved for future use.
Application Error     0x80 – 0xFF  Application error code defined by a higher 
                                   layer specification.

Note that iOS has certain issues where arbitrary error codes show up. For example, if you fail to answer a request as a peripheral app within a certain time, the returned error code does not have any meaning.

The real error codes are always only visible in warnings that are printed to the console. The NSError doesn't provide any detailed information in any case with CoreBluetooth I encountered so far.

Answer 2

Apple's documentation contains a list of CoreBluetooth Constants which contains most error codes you'll receive back from the framework.

I've also started a Wikia site for CoreBluetooth to collect additional information about the circumstances under which people encounter specific errors.