There is a problem if two (or more) users on the same machine (for example root and user) run juffed with "open with existing instance" option set. This option works only for the first one who sets it on.
Attached patch makes the socket per user. Tested on Juffed 0.6.1 on Pardus Linux.
The username or socket path should be probably stored in private static member variable in AppInfo initialized in (new file) AppInfo.cpp. But AppInfo.h is included in both juffed binary and libjuff.so and I think the username should be only in binary in this case.
David Stegbauer, daaste - gmail - com