How does IPython modify the sys.path?

[Daniel Mark]

Hello all:

I installed IPython on my XP machine today and find that my sys.path
has been changed
as follows:

>> import sys
>> print  sys.path

['',
 'C:\\Program Files\\Python24\\scripts',
 'C:\\WINDOWS\\system32\\python24.zip',
 'C:\\Documents and Settings\\Daniel\\Desktop',
 'C:\\Program Files\\Python24\\DLLs',
 'C:\\Program Files\\Python24\\lib',
 'C:\\Program Files\\Python24\\lib\\plat-win',
 'C:\\Program Files\\Python24\\lib\\lib-tk',
 'C:\\Program Files\\Python24',
 'C:\\Program Files\\Python24\\lib\\site-packages',
 'C:\\Program Files\\Python24\\lib\\site-packages\\PIL',
 'C:\\Program Files\\Python24\\lib\\site-packages\\win32',
 'C:\\Program Files\\Python24\\lib\\site-packages\\win32\\lib',
 'C:\\Program Files\\Python24\\lib\\site-packages\\Pythonwin',
 'C:\\Program Files\\Python24\\lib\\site-packages\\wx-2.6-msw-ansi',
 'C:\\Program Files\\Python24\\lib\\site-packages\\reportlab_2_0',
 'C:\\Program Files\\Python24\\lib\\site-packages\\IPython/Extensions',
 'C:\\Documents and Settings\\Daniel\\_ipython']


Obviously, IPython changed my sys.path and added an entry in the end as
"C:\\Documents and Settings\\Daniel\\_ipython'"


However, I cannot figure out how IPython can change my sys.path.

I refer to all the following sources
1> http://www.python.org/doc/current/inst/search-path.html  Installing
Python Modules
2> KEY_LOCAL_MACHINE\Software\Python\PythonCore\2.4\PythonPath
3> My machine has no environment variable  "PYTHONPATH"
4> There is no *.pth file under
C:\Program Files\Python24\Lib\site-packages
that contains that information (i.e. C:\\Documents and
Settings\\Daniel\\_ipython)


So how dos IPython modify my sys.path without trace???



Thank you very much!
-Daniel