How can I obtain a call graph of a Python program?

Environment

• Red Hat Enterprise Linux Server 5
• Red Hat Enterprise Linux Server 6

Issue

I would like to obtain a callgraph of a Python application as to find the sequence of calls leading to a particular error.

Resolution

Run the application with the Content from docs.python.org is not included.trace module which is part of the python package:

$ python -m trace --trace YOUR_APPLICATION

For example to write the call trace to the console:

$ python -m trace --trace /usr/share/system-config-users/system-config-users.py 
 --- modulename: threading, funcname: settrace
threading.py(90):     _trace_hook = func
 --- modulename: system-config-users, funcname: <module>
system-config-users.py(25): import sys
system-config-users.py(26): import signal
system-config-users.py(27): import libuser
system-config-users.py(29): signal.signal (signal.SIGINT, signal.SIG_DFL)
system-config-users.py(31): import gettext
 --- modulename: gettext, funcname: <module>
gettext.py(11): """
....
gettext.py(448):         if lang == 'C':
gettext.py(449):             break
gettext.py(456):     return result
gettext.py(468):     if not mofiles:
gettext.py(469):         if fallback:
gettext.py(471):         raise IOError(ENOENT, 'No translation file found for domain', domain)
gettext.py(541):     except IOError:
gettext.py(542):         return message
system-config-users requires a currently running X server.
system-config-users.py(39):     sys.exit(0)

For example to write the call trace to a file:

$ python -m trace --trace /usr/share/system-config-users/system-config-users.py > /tmp/scu.python-trace.txt

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