Module sys
[hide private]
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Module sys

This module provides access to some objects used or maintained by the
interpreter and to functions that interact strongly with the interpreter.

Dynamic objects:

argv -- command line arguments; argv[0] is the script pathname if known
path -- module search path; path[0] is the script directory, else ''
modules -- dictionary of loaded modules

displayhook -- called to show results in an interactive session
excepthook -- called to handle any uncaught exception other than SystemExit
  To customize printing in an interactive session or to install a custom
  top-level exception handler, assign other functions to replace these.

exitfunc -- if sys.exitfunc exists, this routine is called when Python exits
  Assigning to sys.exitfunc is deprecated; use the atexit module instead.

stdin -- standard input file object; used by raw_input() and input()
stdout -- standard output file object; used by the print statement
stderr -- standard error object; used for error messages
  By assigning other file objects (or objects that behave like files)
  to these, it is possible to redirect all of the interpreter's I/O.

last_type -- type of last uncaught exception
last_value -- value of last uncaught exception
last_traceback -- traceback of last uncaught exception
  These three are only available in an interactive session after a
  traceback has been printed.

exc_type -- type of exception currently being handled
exc_value -- value of exception currently being handled
exc_traceback -- traceback of exception currently being handled
  The function exc_info() should be used instead of these three,
  because it is thread-safe.

Static objects:

maxint -- the largest supported integer (the smallest is -maxint-1)
maxunicode -- the largest supported character
builtin_module_names -- tuple of module names built into this interpreter
version -- the version of this interpreter as a string
version_info -- version information as a tuple
hexversion -- version information encoded as a single integer
copyright -- copyright notice pertaining to this interpreter
platform -- platform identifier
executable -- pathname of this Python interpreter
prefix -- prefix used to find the Python library
exec_prefix -- prefix used to find the machine-specific Python library
__stdin__ -- the original stdin; don't touch!
__stdout__ -- the original stdout; don't touch!
__stderr__ -- the original stderr; don't touch!
__displayhook__ -- the original displayhook; don't touch!
__excepthook__ -- the original excepthook; don't touch!

Functions:

displayhook() -- print an object to the screen, and save it in __builtin__._
excepthook() -- print an exception and its traceback to sys.stderr
exc_info() -- return thread-safe information about the current exception
exc_clear() -- clear the exception state for the current thread
exit() -- exit the interpreter by raising SystemExit
getdlopenflags() -- returns flags to be used for dlopen() calls
getrefcount() -- return the reference count for an object (plus one :-)
getrecursionlimit() -- return the max recursion depth for the interpreter
setcheckinterval() -- control how often the interpreter checks for events
setdlopenflags() -- set the flags to be used for dlopen() calls
setprofile() -- set the global profiling function
setrecursionlimit() -- set the max recursion depth for the interpreter
settrace() -- set the global debug tracing function

Functions [hide private]
None
__displayhook__(object)
Print an object to sys.stdout and also save it in __builtin__.
None
__excepthook__(exctype, value, traceback)
Handle an exception by displaying it with a traceback on sys.stderr.
dictionary
_current_frames()
Return a dictionary mapping each current thread T's thread id to T's current stack frame.
frameobject
_getframe(depth=...)
Return a frame object from the call stack.
object
call_tracing(func, args)
Call func(*args), while tracing is enabled.
tuple of integers
callstats()
Return a tuple of function call statistics, if CALL_PROFILE was defined when Python was built.
None
displayhook(object)
Print an object to sys.stdout and also save it in __builtin__.
None
exc_clear()
Clear global information on the current exception.
(type, value, traceback)
exc_info()
Return information about the most recent exception caught by an except clause in the current stack frame or in an older stack frame.
None
excepthook(exctype, value, traceback)
Handle an exception by displaying it with a traceback on sys.stderr.
 
exit(status=...)
Exit the interpreter by raising SystemExit(status).
current check interval; see setcheckinterval().
getcheckinterval()
string
getdefaultencoding()
Return the current default string encoding used by the Unicode implementation.
int
getdlopenflags()
Return the current value of the flags that are used for dlopen() calls.
string
getfilesystemencoding()
Return the encoding used to convert Unicode filenames in operating system filenames.
 
getrecursionlimit()
Return the current value of the recursion limit, the maximum depth of the Python interpreter stack.
integer
getrefcount(object)
Return the reference count of object.
 
setcheckinterval(n)
Tell the Python interpreter to check for asynchronous events every n instructions.
None
setdlopenflags(n)
Set the flags that will be used for dlopen() calls.
 
setprofile(function)
Set the profiling function.
 
setrecursionlimit(n)
Set the maximum depth of the Python interpreter stack to n.
 
settrace(function)
Set the global debug tracing function.
Variables [hide private]
  __stderr__ = <open file '<stderr>', mode 'w' at 0x401a60b0>
  __stdin__ = <open file '<stdin>', mode 'r' at 0x401a6020>
  __stdout__ = <open file '<stdout>', mode 'w' at 0x401a6068>
  api_version = 1013
  argv = ['src/epydoc/cli.py', '-o', 'html/stdlib', '--css', 'wh...
  builtin_module_names = ('__builtin__', '__main__', '_ast', '_c...
  byteorder = 'little'
  copyright = 'Copyright (c) 2001-2006 Python Software Foundatio...
  exc_type = None
  exec_prefix = '/usr'
  executable = '/usr/bin/python2.5'
  hexversion = 33882352
  maxint = 2147483647
  maxunicode = 1114111
  meta_path = []
  modules = {'BaseHTTPServer': <module 'BaseHTTPServer' from '/u...
  path = ['/home/edloper/newdata/projects/epydoc/src/epydoc', '/...
  path_hooks = [<type 'zipimport.zipimporter'>]
  path_importer_cache = {'': None, '/home/edloper/newdata/projec...
  platform = 'linux2'
  prefix = '/usr'
  stderr = <open file '<stderr>', mode 'w' at 0x401a60b0>
  stdin = <open file '<stdin>', mode 'r' at 0x401a6020>
  stdout = <open file '<stdout>', mode 'w' at 0x401a6068>
  subversion = ('CPython', 'branches/release25-maint', '')
  version = '2.5 (release25-maint, Dec 9 2006, 14:35:53) \n[GCC...
  version_info = (2, 5, 0, 'final', 0)
  warnoptions = []
Function Details [hide private]

_current_frames()

 

Return a dictionary mapping each current thread T's thread id to T's current stack frame.

This function should be used for specialized purposes only.

Returns: dictionary

_getframe(depth=...)

 

Return a frame object from the call stack. If optional integer depth is given, return the frame object that many calls below the top of the stack. If that is deeper than the call stack, ValueError is raised. The default for depth is zero, returning the frame at the top of the call stack.

This function should be used for internal and specialized purposes only.

Returns: frameobject

call_tracing(func, args)

 

Call func(*args), while tracing is enabled. The tracing state is saved, and restored afterwards. This is intended to be called from a debugger from a checkpoint, to recursively debug some other code.

Returns: object

callstats()

 
Return a tuple of function call statistics, if CALL_PROFILE was defined
when Python was built.  Otherwise, return None.

When enabled, this function returns detailed, implementation-specific
details about the number of function calls executed. The return value is
a 11-tuple where the entries in the tuple are counts of:
0. all function calls
1. calls to PyFunction_Type objects
2. PyFunction calls that do not create an argument tuple
3. PyFunction calls that do not create an argument tuple
   and bypass PyEval_EvalCodeEx()
4. PyMethod calls
5. PyMethod calls on bound methods
6. PyType calls
7. PyCFunction calls
8. generator calls
9. All other calls
10. Number of stack pops performed by call_function()

Returns: tuple of integers

exc_clear()

 

Clear global information on the current exception. Subsequent calls to exc_info() will return (None,None,None) until another exception is raised in the current thread or the execution stack returns to a frame where another exception is being handled.

Returns: None

exit(status=...)

 

Exit the interpreter by raising SystemExit(status). If the status is omitted or None, it defaults to zero (i.e., success). If the status is numeric, it will be used as the system exit status. If it is another kind of object, it will be printed and the system exit status will be one (i.e., failure).

getdlopenflags()

 

Return the current value of the flags that are used for dlopen() calls. The flag constants are defined in the dl module.

Returns: int

getrecursionlimit()

 

Return the current value of the recursion limit, the maximum depth of the Python interpreter stack. This limit prevents infinite recursion from causing an overflow of the C stack and crashing Python.

getrefcount(object)

 

Return the reference count of object. The count returned is generally one higher than you might expect, because it includes the (temporary) reference as an argument to getrefcount().

Returns: integer

setcheckinterval(n)

 

Tell the Python interpreter to check for asynchronous events every n instructions. This also affects how often thread switches occur.

setdlopenflags(n)

 

Set the flags that will be used for dlopen() calls. Among other things, this will enable a lazy resolving of symbols when importing a module, if called as sys.setdlopenflags(0) To share symbols across extension modules, call as sys.setdlopenflags(dl.RTLD_NOW|dl.RTLD_GLOBAL)

Returns: None

setprofile(function)

 

Set the profiling function. It will be called on each function call and return. See the profiler chapter in the library manual.

setrecursionlimit(n)

 

Set the maximum depth of the Python interpreter stack to n. This limit prevents infinite recursion from causing an overflow of the C stack and crashing Python. The highest possible limit is platform- dependent.

settrace(function)

 

Set the global debug tracing function. It will be called on each function call. See the debugger chapter in the library manual.


Variables Details [hide private]

argv

Value:
['src/epydoc/cli.py',
 '-o',
 'html/stdlib',
 '--css',
 'white',
 '--name',
 'Python Standard Library',
 '--url',
...

builtin_module_names

Value:
('__builtin__',
 '__main__',
 '_ast',
 '_codecs',
 '_sre',
 '_symtable',
 '_types',
 'errno',
...

copyright

Value:
'''Copyright (c) 2001-2006 Python Software Foundation.
All Rights Reserved.

Copyright (c) 2000 BeOpen.com.
All Rights Reserved.

Copyright (c) 1995-2001 Corporation for National Research Initiatives.
All Rights Reserved.
...

modules

Value:
{'BaseHTTPServer': <module 'BaseHTTPServer' from '/usr/lib/python2.5/B\
aseHTTPServer.pyc'>,
 'Bastion': <module 'Bastion' from '/usr/lib/python2.5/Bastion.pyc'>,
 'CDROM': <module 'CDROM' from '/usr/lib/python2.5/plat-linux2/CDROM.p\
yc'>,
 'CGIHTTPServer': <module 'CGIHTTPServer' from '/usr/lib/python2.5/CGI\
HTTPServer.pyc'>,
 'Canvas': <module 'Canvas' from '/usr/lib/python2.5/lib-tk/Canvas.pyc\
...

path

Value:
['/home/edloper/newdata/projects/epydoc/src/epydoc',
 '/home/edloper/newdata/projects/epydoc/src',
 '/usr/lib/python25.zip',
 '/usr/lib/python2.5',
 '/usr/lib/python2.5/plat-linux2',
 '/usr/lib/python2.5/lib-tk',
 '/usr/lib/python2.5/lib-dynload',
 '/usr/local/lib/python2.5/site-packages',
...

path_importer_cache

Value:
{'': None,
 '/home/edloper/newdata/projects/docutils': None,
 '/home/edloper/newdata/projects/docutils/docutils': None,
 '/home/edloper/newdata/projects/docutils/docutils/languages': None,
 '/home/edloper/newdata/projects/docutils/docutils/parsers': None,
 '/home/edloper/newdata/projects/docutils/docutils/parsers/rst': None,
 '/home/edloper/newdata/projects/docutils/docutils/parsers/rst/directi\
ves': None,
...

version

Value:
'''2.5 (release25-maint, Dec  9 2006, 14:35:53) 
[GCC 4.1.2 20061115 (prerelease) (Debian 4.1.1-20)]'''