27.5.5 gdb/mi Thread Information
Whenever gdb has to report an information about a thread, it
uses a tuple with the following fields:
     
id- The numeric id assigned to the thread by gdb.  This field is
always present.
     
 target-id- Target-specific string identifying the thread.  This field is always present.
     
 details- Additional information about the thread provided by the target. 
It is supposed to be human-readable and not interpreted by the
frontend.  This field is optional.
     
 state- Either `stopped' or `running', depending on whether the
thread is presently running.  This field is always present.
     
 core- The value of this field is an integer number of the processor core the
thread was last seen on.  This field is optional.