27.5.1 gdb/mi Result Records

In addition to a number of out-of-band notifications, the response to a gdb/mi command includes one of the following result indications:

"^done" [ "," results ]
The synchronous operation was successful, results are the return values.
"^running"
This result record is equivalent to ^done. Historically, it was output instead of ^done if the command has resumed the target. This behaviour is maintained for backward compatibility, but all frontends should treat ^done and ^running identically and rely on the *running output record to determine which threads are resumed.
"^connected"
gdb has connected to a remote target.
"^error" "," c-string
The operation failed. The c-string contains the corresponding error message.
"^exit"
gdb has terminated.