Rev 2425: doc BZR_PDB and sigquit in http://sourcefrog.net/bzr/breakin

[Martin Pool]

At http://sourcefrog.net/bzr/breakin

------------------------------------------------------------
revno: 2425
revision-id: mbp at sourcefrog.net-20070417052419-x9erzvt3xtzuhdvf
parent: mbp at sourcefrog.net-20070417043912-2mwgd3htam3a5uq2
committer: Martin Pool <mbp at sourcefrog.net>
branch nick: breakin
timestamp: Tue 2007-04-17 15:24:19 +1000
message:
  doc BZR_PDB and sigquit
modified:
  HACKING                        HACKING-20050805200004-2a5dc975d870f78c
=== modified file 'HACKING'
--- a/HACKING	2007-04-11 10:46:19 +0000
+++ b/HACKING	2007-04-17 05:24:19 +0000
@@ -475,6 +475,24 @@
 
 
 
+Debugging
+=========
+
+Bazaar has a few facilities to help debug problems by going into pdb_, the
+Python debugger.
+
+http://docs.python.org/lib/debugger-commands.html
+
+If the ``BZR_PDB`` environment variable is set 
+then bzr will go into pdb post-mortem mode when an unhandled exception
+occurs.
+
+If you send a SIGQUIT signal to bzr, which can be done by pressing C-\ on Unix,
+bzr will go into the debugger immediately.  You can continue execution by
+typing ``c``.
+
+
+
 Jargon
 ======