"""Append module search paths for third-party packages to sys.path.
****************************************************************
* This module is automatically imported during initialization. *
****************************************************************
In earlier versions of Python (up to 1.5a3), scripts or modules that
needed to use site-specific modules would place ``import site''
somewhere near the top of their code. Because of the automatic
import, this is no longer necessary (but code that does it still
works).
This will append site-specific paths to to the module search path. On
Unix, it starts with sys.prefix and sys.exec_prefix (if different) and
appends lib/python<version>/site-packages as well as lib/site-python.
On other platforms (mainly Mac and Windows), it uses just sys.prefix
(and sys.exec_prefix, if different, but this is unlikely). The
resulting directories, if they exist, are appended to sys.path, and
also inspected for path configuration files.
A path configuration file is a file whose name has the form
<package>.pth; its contents are additional directories (one per line)
to be added to sys.path. Non-existing directories (or
non-directories) are never added to sys.path; no directory is added to
sys.path more than once. Blank lines and lines beginning with
\code{#} are skipped.
For example, suppose sys.prefix and sys.exec_prefix are set to
/usr/local and there is a directory /usr/local/lib/python1.5/site-packages
with three subdirectories, foo, bar and spam, and two path
configuration files, foo.pth and bar.pth. Assume foo.pth contains the
following:
# foo package configuration
foo
bar
bletch
and bar.pth contains:
# bar package configuration
bar
Then the following directories are added to sys.path, in this order:
/usr/local/lib/python1.5/site-packages/bar
/usr/local/lib/python1.5/site-packages/foo
Note that bletch is omitted because it doesn't exist; bar precedes foo
because bar.pth comes alphabetically before foo.pth; and spam is
omitted because it is not mentioned in either path configuration file.
After these path manipulations, an attempt is made to import a module
named sitecustomize, which can perform arbitrary additional
site-specific customizations. If this import fails with an
ImportError exception, it is silently ignored.
"""
import sys, os
def addsitedir(sitedir):
if sitedir not in sys.path:
sys.path.append(sitedir) # Add path component
try:
names = os.listdir(sitedir)
except os.error:
return
names = map(os.path.normcase, names)
names.sort()
for name in names:
if name[-4:] == ".pth":
addpackage(sitedir, name)
def addpackage(sitedir, name):
fullname = os.path.join(sitedir, name)
try:
f = open(fullname)
except IOError:
return
while 1:
dir = f.readline()
if not dir:
break
if dir[0] == '#':
continue
if dir[-1] == '\n':
dir = dir[:-1]
dir = os.path.join(sitedir, dir)
if dir not in sys.path and os.path.exists(dir):
sys.path.append(dir)
prefixes = [sys.prefix]
if sys.exec_prefix != sys.prefix:
prefixes.append(sys.exec_prefix)
for prefix in prefixes:
if prefix:
if os.sep == '/':
sitedirs = [os.path.join(prefix,
"lib",
"python" + sys.version[:3],
"site-packages"),
os.path.join(prefix, "lib", "site-python")]
else:
sitedirs = [prefix]
for sitedir in sitedirs:
if os.path.isdir(sitedir):
addsitedir(sitedir)
# Define new built-ins 'quit' and 'exit'.
# These are simply strings that display a hint on how to exit.
if os.sep == ':':
exit = 'Use Cmd-Q to quit.'
elif os.sep == '\\':
exit = 'Use Ctrl-Z plus Return to exit.'
else:
exit = 'Use Ctrl-D (i.e. EOF) to exit.'
import __builtin__
__builtin__.quit = __builtin__.exit = exit
del exit
try:
import sitecustomize # Run arbitrary site specific code
except ImportError:
pass # No site customization module
def _test():
print "sys.path = ["
for dir in sys.path:
print " %s," % `dir`
print "]"
if __name__ == '__main__':
_test()
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