Lines from 'ps auxef':

martin   14538  0.7  4.9 315696 102556 ?       Sl   22:34   0:03 /usr/bin/python2.5 /usr/bin/update-manager GPG_AGENT_INFO=/tmp/gpg-33f6lZ/S.gpg-agent:5682:1 SHELL=/bin/bash USER=martin USERNAME=martin PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/bin/X11:/usr/games DESKTOP_SESSION=gnome GDM_XSERVER_LOCATION=local PWD=/home/martin LANG=de_DE.UTF-8 GDM_LANG=de_DE.UTF-8 GDMSESSION=gnome SHLVL=0 HOME=/home/martin LANGUAGE=de_DE.UTF-8 LOGNAME=martin XDG_DATA_DIRS=/usr/local/share/:/usr/share/:/usr/share/gdm/ WINDOWPATH=7 DISPLAY=:0.0 XAUTHORITY=/home/martin/.Xauthority SSH_AUTH_SOCK=/tmp/ssh-itCusd5522/agent.5522 SSH_AGENT_PID=5686 GTK_RC_FILES=/etc/gtk/gtkrc:/home/martin/.gtkrc-1.2-gnome2 SESSION_MANAGER=local/garrett:/tmp/.ICE-unix/5522 GNOME_KEYRING_SOCKET=/tmp/keyring-pmpmZO/socket DBUS_SESSION_BUS_ADDRESS=unix:abstract=/tmp/dbus-3GEgfndi2z,guid=e66959cfca169d440938cc0046d47183 GNOME_DESKTOP_SESSION_ID=Default
martin   14548  0.0  0.2 118128  5936 ?        S    22:34   0:00  \_ gksu --desktop /usr/share/applications/update-manager.desktop -- /usr/sbin/synaptic --hide-main-window --non-interactive --parent-window-id 65011715 --progress-str Bitte warten Sie, dieser Vorgang kann etwas Zeit in Anspruch nehmen. --finish-str Die Aktualisierung ist abgeschlossen --set-selections-file /tmp/tmprACguR GPG_AGENT_INFO=/tmp/gpg-33f6lZ/S.gpg-agent:5682:1 SHELL=/bin/bash USER=martin USERNAME=martin PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/bin/X11:/usr/games DESKTOP_SESSION=gnome GDM_XSERVER_LOCATION=local PWD=/home/martin LANG=de_DE.UTF-8 GDM_LANG=de_DE.UTF-8 GDMSESSION=gnome SHLVL=0 HOME=/home/martin LANGUAGE=de_DE.UTF-8 LOGNAME=martin XDG_DATA_DIRS=/usr/local/share/:/usr/share/:/usr/share/gdm/ WINDOWPATH=7 DISPLAY=:0.0 XAUTHORITY=/home/martin/.Xauthority SSH_AUTH_SOCK=/tmp/ssh-itCusd5522/agent.5522 SSH_AGENT_PID=5686 GTK_RC_FILES=/etc/gtk/gtkrc:/home/martin/.gtkrc-1.2-gnome2 SESSION_MANAGER=local/garrett:/tmp/.ICE-unix/5522 GNOME_KEYRING_SOCKET=/tmp/keyring-pmpmZO/socket DBUS_SESSION_BUS_ADDRESS=unix:abstract=/tmp/dbus-3GEgfndi2z,guid=e66959cfca169d440938cc0046d47183 GNOME_DESKTOP_SESSION_ID=Default APT_LISTCHANGES_FRONTEND=none
root     14549  0.4  2.8 201296 58520 ?        Ss   22:34   0:02      \_ /usr/sbin/synaptic --hide-main-window --non-interactive --parent-window-id 65011715 --progress-str Bitte warten Sie, dieser Vorgang kann etwas Zeit in Anspruch nehmen. --finish-str Die Aktualisierung ist abgeschlossen --set-selections-file /tmp/tmprACguR
root     14551  0.0  0.0  17160   796 ?        S    22:34   0:00          \_ gnome-pty-helper
root     14552  3.7  1.0 181552 20856 pts/1    Ss+  22:34   0:17          \_ /usr/sbin/synaptic --hide-main-window --non-interactive --parent-window-id 65011715 --progress-str Bitte warten Sie, dieser Vorgang kann etwas Zeit in Anspruch nehmen. --finish-str Die Aktualisierung ist abgeschlossen --set-selections-file /tmp/tmprACguR
root     14799  2.7  0.0      0     0 ?        Zs   22:35   0:11              \_ [dpkg] <defunct>


Debugging attempt: (seems to hang at

martin@garrett:~$ sudo gdb /usr/bin/synaptic 14552
GNU gdb 6.6-debian
Copyright (C) 2006 Free Software Foundation, Inc.
GDB is free software, covered by the GNU General Public License, and you are
welcome to change it and/or distribute copies of it under certain conditions.
Type "show copying" to see the conditions.
There is absolutely no warranty for GDB.  Type "show warranty" for details.
This GDB was configured as "x86_64-linux-gnu"...
/usr/bin/synaptic: No such file or directory.
Attaching to process 14552
Reading symbols from /usr/sbin/synaptic...(no debugging symbols found)...done.
Using host libthread_db library "/lib/libthread_db.so.1".
Reading symbols from /usr/lib/libapt-pkg-libc6.6-6.so.4.5...(no debugging symbols found)...done.
Loaded symbols for /usr/lib/libapt-pkg-libc6.6-6.so.4.5
Reading symbols from /usr/lib/libapt-inst-libc6.6-6.so.1.1...(no debugging symbols found)...done.
Loaded symbols for /usr/lib/libapt-inst-libc6.6-6.so.1.1
Reading symbols from /usr/lib/libglade-2.0.so.0...(no debugging symbols found)...done.
Loaded symbols for /usr/lib/libglade-2.0.so.0
Reading symbols from /usr/lib/libgtk-x11-2.0.so.0...Reading symbols from /usr/lib/debug/usr/lib/libgtk-x11-2.0.so.0.1106.0...done.
done.
Loaded symbols for /usr/lib/libgtk-x11-2.0.so.0
Reading symbols from /usr/lib/libxml2.so.2...done.
Loaded symbols for /usr/lib/libxml2.so.2
Reading symbols from /usr/lib/libgdk-x11-2.0.so.0...Reading symbols from /usr/lib/debug/usr/lib/libgdk-x11-2.0.so.0.1106.0...done.
done.
Loaded symbols for /usr/lib/libgdk-x11-2.0.so.0
Reading symbols from /usr/lib/libatk-1.0.so.0...done.
Loaded symbols for /usr/lib/libatk-1.0.so.0
Reading symbols from /usr/lib/libgdk_pixbuf-2.0.so.0...done.
Loaded symbols for /usr/lib/libgdk_pixbuf-2.0.so.0
Reading symbols from /usr/lib/libpangocairo-1.0.so.0...done.
Loaded symbols for /usr/lib/libpangocairo-1.0.so.0
Reading symbols from /usr/lib/libfontconfig.so.1...done.
Loaded symbols for /usr/lib/libfontconfig.so.1
Reading symbols from /usr/lib/libXext.so.6...done.
Loaded symbols for /usr/lib/libXext.so.6
Reading symbols from /usr/lib/libXrender.so.1...done.
Loaded symbols for /usr/lib/libXrender.so.1
Reading symbols from /usr/lib/libXinerama.so.1...done.
Loaded symbols for /usr/lib/libXinerama.so.1
Reading symbols from /usr/lib/libXi.so.6...done.
Loaded symbols for /usr/lib/libXi.so.6
Reading symbols from /usr/lib/libXrandr.so.2...done.
Loaded symbols for /usr/lib/libXrandr.so.2
Reading symbols from /usr/lib/libXcursor.so.1...done.
Loaded symbols for /usr/lib/libXcursor.so.1
Reading symbols from /usr/lib/libXcomposite.so.1...done.
Loaded symbols for /usr/lib/libXcomposite.so.1
Reading symbols from /usr/lib/libXdamage.so.1...done.
Loaded symbols for /usr/lib/libXdamage.so.1
Reading symbols from /usr/lib/libcairo.so.2...done.
Loaded symbols for /usr/lib/libcairo.so.2
Reading symbols from /usr/lib/libX11.so.6...done.
Loaded symbols for /usr/lib/libX11.so.6
Reading symbols from /usr/lib/libXfixes.so.3...done.
Loaded symbols for /usr/lib/libXfixes.so.3
Reading symbols from /usr/lib/libpango-1.0.so.0...done.
Loaded symbols for /usr/lib/libpango-1.0.so.0
Reading symbols from /usr/lib/libgobject-2.0.so.0...done.
Loaded symbols for /usr/lib/libgobject-2.0.so.0
Reading symbols from /usr/lib/libgmodule-2.0.so.0...done.
Loaded symbols for /usr/lib/libgmodule-2.0.so.0
Reading symbols from /lib/libdl.so.2...Reading symbols from /usr/lib/debug/lib/libdl-2.6.1.so...done.
done.
Loaded symbols for /lib/libdl.so.2
Reading symbols from /usr/lib/libglib-2.0.so.0...done.
Loaded symbols for /usr/lib/libglib-2.0.so.0
Reading symbols from /usr/lib/libvte.so.9...done.
Loaded symbols for /usr/lib/libvte.so.9
Reading symbols from /usr/lib/libXft.so.2...done.
Loaded symbols for /usr/lib/libXft.so.2
Reading symbols from /usr/lib/libpangoxft-1.0.so.0...done.
Loaded symbols for /usr/lib/libpangoxft-1.0.so.0
Reading symbols from /usr/lib/libpangox-1.0.so.0...done.
Loaded symbols for /usr/lib/libpangox-1.0.so.0
Reading symbols from /lib/libm.so.6...Reading symbols from /usr/lib/debug/lib/libm-2.6.1.so...done.
done.
Loaded symbols for /lib/libm.so.6
Reading symbols from /usr/lib/libpangoft2-1.0.so.0...done.
Loaded symbols for /usr/lib/libpangoft2-1.0.so.0
Reading symbols from /usr/lib/liblaunchpad-integration.so.0...done.
Loaded symbols for /usr/lib/liblaunchpad-integration.so.0
Reading symbols from /lib/libpthread.so.0...Reading symbols from /usr/lib/debug/lib/libpthread-2.6.1.so...done.
[Thread debugging using libthread_db enabled]
[New Thread 47499913769456 (LWP 14552)]
done.
Loaded symbols for /lib/libpthread.so.0
Reading symbols from /usr/lib/libstdc++.so.6...done.
Loaded symbols for /usr/lib/libstdc++.so.6
Reading symbols from /lib/libgcc_s.so.1...done.
Loaded symbols for /lib/libgcc_s.so.1
Reading symbols from /lib/libc.so.6...Reading symbols from /usr/lib/debug/lib/libc-2.6.1.so...done.
done.
Loaded symbols for /lib/libc.so.6
Reading symbols from /lib/libutil.so.1...Reading symbols from /usr/lib/debug/lib/libutil-2.6.1.so...done.
done.
Loaded symbols for /lib/libutil.so.1
Reading symbols from /usr/lib/libz.so.1...done.
Loaded symbols for /usr/lib/libz.so.1
Reading symbols from /usr/lib/libfreetype.so.6...done.
Loaded symbols for /usr/lib/libfreetype.so.6
Reading symbols from /usr/lib/libexpat.so.1...done.
Loaded symbols for /usr/lib/libexpat.so.1
Reading symbols from /usr/lib/libXau.so.6...done.
Loaded symbols for /usr/lib/libXau.so.6
Reading symbols from /usr/lib/libpng12.so.0...done.
Loaded symbols for /usr/lib/libpng12.so.0
Reading symbols from /usr/lib/libXdmcp.so.6...done.
Loaded symbols for /usr/lib/libXdmcp.so.6
Reading symbols from /lib/ld-linux-x86-64.so.2...Reading symbols from /usr/lib/debug/lib/ld-2.6.1.so...done.
done.
Loaded symbols for /lib64/ld-linux-x86-64.so.2
Reading symbols from /usr/lib/libSM.so.6...done.
Loaded symbols for /usr/lib/libSM.so.6
Reading symbols from /usr/lib/libICE.so.6...done.
Loaded symbols for /usr/lib/libICE.so.6
Reading symbols from /usr/lib/libncurses.so.5...done.
Loaded symbols for /usr/lib/libncurses.so.5
Reading symbols from /lib/libnss_compat.so.2...Reading symbols from /usr/lib/debug/lib/libnss_compat-2.6.1.so...done.
done.
Loaded symbols for /lib/libnss_compat.so.2
Reading symbols from /lib/libnsl.so.1...Reading symbols from /usr/lib/debug/lib/libnsl-2.6.1.so...done.
done.
Loaded symbols for /lib/libnsl.so.1
Reading symbols from /lib/libnss_nis.so.2...Reading symbols from /usr/lib/debug/lib/libnss_nis-2.6.1.so...done.
done.
Loaded symbols for /lib/libnss_nis.so.2
Reading symbols from /lib/libnss_files.so.2...Reading symbols from /usr/lib/debug/lib/libnss_files-2.6.1.so...done.
done.
Loaded symbols for /lib/libnss_files.so.2
Reading symbols from /usr/lib/gconv/ISO8859-1.so...Reading symbols from /usr/lib/debug/usr/lib/gconv/ISO8859-1.so...done.
done.
Loaded symbols for /usr/lib/gconv/ISO8859-1.so
Reading symbols from /usr/lib/gtk-2.0/2.10.0/engines/libubuntulooks.so...done.
Loaded symbols for /usr/lib/gtk-2.0/2.10.0/engines/libubuntulooks.so
Reading symbols from /usr/lib/gtk-2.0/2.10.0/loaders/libpixbufloader-png.so...Reading symbols from /usr/lib/debug/usr/lib/gtk-2.0/2.10.0/loaders/libpixbufloader-png.so...done.
done.
Loaded symbols for /usr/lib/gtk-2.0/2.10.0/loaders/libpixbufloader-png.so
Reading symbols from /usr/lib/pango/1.6.0/modules/pango-basic-fc.so...done.
Loaded symbols for /usr/lib/pango/1.6.0/modules/pango-basic-fc.so
Reading symbols from /usr/lib/gtk-2.0/2.10.0/loaders/libpixbufloader-xpm.so...Reading symbols from /usr/lib/debug/usr/lib/gtk-2.0/2.10.0/loaders/libpixbufloader-xpm.so...done.
done.
Loaded symbols for /usr/lib/gtk-2.0/2.10.0/loaders/libpixbufloader-xpm.so
0x00002b336d7d8ec0 in __read_nocancel ()
   from /lib/libpthread.so.0
(gdb) where
#0  0x00002b336d7d8ec0 in __read_nocancel () from /lib/libpthread.so.0
#1  0x00002b33689aa26c in pkgDPkgPM::DoTerminalPty () from /usr/lib/libapt-pkg-libc6.6-6.so.4.5
#2  0x00002b33689af0d0 in pkgDPkgPM::Go () from /usr/lib/libapt-pkg-libc6.6-6.so.4.5
#3  0x000000000042d323 in ?? ()
#4  0x000000000046ac0f in ?? ()
#5  0x000000000043dfd8 in ?? ()
#6  0x0000000000415677 in ?? ()
#7  0x00002b336df1eb44 in __libc_start_main () from /lib/libc.so.6
#8  0x0000000000413569 in ?? ()
#9  0x00007fff423adad8 in ?? ()
#10 0x0000000000000000 in ?? ()
(gdb) cont
Continuing.

Program received signal SIGINT, Interrupt.
[Switching to Thread 47499913769456 (LWP 14552)]
0x00002b336d7d8ec0 in __read_nocancel () from /lib/libpthread.so.0
(gdb) where
#0  0x00002b336d7d8ec0 in __read_nocancel () from /lib/libpthread.so.0
#1  0x00002b33689aa26c in pkgDPkgPM::DoTerminalPty () from /usr/lib/libapt-pkg-libc6.6-6.so.4.5
#2  0x00002b33689af0d0 in pkgDPkgPM::Go () from /usr/lib/libapt-pkg-libc6.6-6.so.4.5
#3  0x000000000042d323 in ?? ()
#4  0x000000000046ac0f in ?? ()
#5  0x000000000043dfd8 in ?? ()
#6  0x0000000000415677 in ?? ()
#7  0x00002b336df1eb44 in __libc_start_main () from /lib/libc.so.6
#8  0x0000000000413569 in ?? ()
#9  0x00007fff423adad8 in ?? ()
#10 0x0000000000000000 in ?? ()
(gdb) step
Single stepping until exit from function __read_nocancel, 
which has no line number information.