When executing the
python command, Python exceptions
uncaught within the Python code are translated to calls to
GDB error-reporting mechanism. If the command that called
python does not handle the error, GDB will
terminate it and print an error message containing the Python
exception name, the associated value, and the Python call stack
backtrace at the point where the exception was raised. Example:
(gdb) python print foo Traceback (most recent call last): File "<string>", line 1, in <module> NameError: name 'foo' is not defined
GDB errors that happen in GDB commands invoked by Python code are converted to Python exceptions. The type of the Python exception depends on the error.
This is the base class for most exceptions generated by GDB.
It is derived from
RuntimeError, for compatibility with earlier
versions of GDB.
If an error occurring in GDB does not fit into some more specific category, then the generated exception will have this type.
This is a subclass of
gdb.error which is thrown when an
operation tried to access invalid memory in the inferior.
User interrupt (via C-c or by typing q at a pagination
prompt) is translated to a Python
In all cases, your exception handler will see the GDB error message as its value and the Python call stack backtrace at the Python statement closest to where the GDB error occured as the traceback.
When implementing GDB commands in Python via
gdb.Command, or functions via
gdb.Function, it is useful
to be able to throw an exception that doesn’t cause a traceback to be
printed. For example, the user may have invoked the command
incorrectly. GDB provides a special exception class that can
be used for this purpose.
When thrown from a command or function, this exception will cause the command or function to fail, but the Python stack will not be displayed. GDB does not throw this exception itself, but rather recognizes it when thrown from user Python code. Example:
(gdb) python >class HelloWorld (gdb.Command): > """Greet the whole world.""" > def __init__ (self): > super (HelloWorld, self).__init__ ("hello-world", gdb.COMMAND_USER) > def invoke (self, args, from_tty): > argv = gdb.string_to_argv (args) > if len (argv) != 0: > raise gdb.GdbError ("hello-world takes no arguments") > print "Hello, World!" >HelloWorld () >end (gdb) hello-world 42 hello-world takes no arguments