To efficiently update the list of threads and their attributes, gdb issues the ‘qXfer:threads:read’ packet (see qXfer threads read) and obtains the XML document with the following structure:
<?xml version="1.0"?> <threads> <thread id="id" core="0"> ... description ... </thread> </threads>
Each ‘thread’ element must have the ‘id’ attribute that identifies the thread (see thread-id syntax). The ‘core’ attribute, if present, specifies which processor core the thread was last executing on. The content of the of ‘thread’ element is interpreted as human-readable auxilliary information.