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PYTHON(1)							     PYTHON(1)



NAME
       python  - an interpreted, interactive, object-oriented programming lan
       guage

SYNOPSIS
       python [ -d ] [ -E ] [ -h ] [ -i ] [ -m module-name ] [ -O ]
	      [ -Q argument ] [ -S ] [ -t ] [ -u ]
	      [ -v ] [ -V ] [ -W argument ] [ -x ]
	      [ -c command | script | - ] [ arguments ]

DESCRIPTION
       Python is an interpreted, interactive, object-oriented programming lan
       guage  that  combines  remarkable power with very clear syntax.	For an
       introduction to programming in Python you are referred  to  the	Python
       Tutorial.  The Python Library Reference documents built-in and standard
       types, constants, functions and modules.  Finally, the Python Reference
       Manual describes the syntax and semantics of the core language in (per
       haps too) much detail.  (These documents may be located via the	INTER
       NET RESOURCES below; they may be installed on your system as well.)

       Pythons basic power can be extended with your own modules written in C
       or C++.	On most  systems  such	modules  may  be  dynamically  loaded.
       Python is also adaptable as an extension language for existing applica
       tions.  See the internal documentation for hints.

       Documentation for installed Python modules and packages can  be	viewed
       by running the pydoc program.

COMMAND LINE OPTIONS
       -c command
	      Specify  the command to execute (see next section).  This termi
	      nates the option list (following options are passed as arguments
	      to the command).

       -d     Turn  on parser debugging output (for wizards only, depending on
	      compilation options).

       -E     Ignore environment variables like PYTHONPATH and PYTHONHOME that
	      modify the behavior of the interpreter.

       -h     Prints the usage for the interpreter executable and exits.

       -i     When  a  script  is passed as first argument or the -c option is
	      used, enter interactive mode after executing the script  or  the
	      command.	It does not read the $PYTHONSTARTUP file.  This can be
	      useful to inspect global variables  or  a  stack	trace  when  a
	      script raises an exception.

       -m module-name
	      Searches	sys.path for the named module and runs the correspond
	      ing .py file as a script.

       -O     Turn on basic optimizations.  This changes the  filename	exten
	      sion  for  compiled  (bytecode)  files from .pyc to .pyo.  Given
	      twice, causes docstrings to be discarded.

       -Q argument
	      Division control; see PEP 238.  The  argument  must  be  one  of
	      "old"  (the  default,  int/int  and  long/long  return an int or
	      long), "new" (new division semantics, i.e. int/int and long/long
	      returns  a float), "warn" (old division semantics with a warning
	      for int/int and long/long), or "warnall" (old division semantics
	      with a warning for all use of the division operator).  For a use
	      of "warnall", see the Tools/scripts/fixdiv.py script.

       -S     Disable the import of the module	site  and  the	site-dependent
	      manipulations of sys.path that it entails.

       -t     Issue  a	warning  when  a source file mixes tabs and spaces for
	      indentation in a way that makes it depend on the worth of a  tab
	      expressed  in  spaces.   Issue an error when the option is given
	      twice.

       -u     Force stdin, stdout and stderr to  be  totally  unbuffered.   On
	      systems  where  it matters, also put stdin, stdout and stderr in
	      binary mode.  Note that there is internal  buffering  in	xread
	      lines(),	readlines()  and  file-object  iterators ("for line in
	      sys.stdin") which is not influenced by  this  option.   To  work
	      around  this, you will want to use "sys.stdin.readline()" inside
	      a "while 1:" loop.

       -v     Print a message each time a module is initialized,  showing  the
	      place  (filename	or  built-in  module) from which it is loaded.
	      When given twice, print a message for each file that is  checked
	      for  when  searching for a module.  Also provides information on
	      module cleanup at exit.

       -V     Prints the Python version number of the executable and exits.

       -W argument
	      Warning control.	Python sometimes  prints  warning  message  to
	      sys.stderr.   A  typical warning message has the following form:
	      file:line: category:  message.   By  default,  each  warning  is
	      printed  once for each source line where it occurs.  This option
	      controls how often warnings are printed.	 Multiple  -W  options
	      may  be  given; when a warning matches more than one option, the
	      action for the last matching option is  performed.   Invalid  -W
	      options  are ignored (a warning message is printed about invalid
	      options when the first warning is issued).  Warnings can also be
	      controlled  from within a Python program using the warnings mod
	      ule.

	      The simplest form of argument is one  of	the  following	action
	      strings  (or  a unique abbreviation): ignore to ignore all warn
	      ings; default to explicitly request the default behavior (print
	      ing  each  warning once per source line); all to print a warning
	      each time it occurs (this may generate many messages if a  warn
	      ing  is  triggered  repeatedly for the same source line, such as
	      inside a loop); module to print each warning only only the first
	      time  it	occurs in each module; once to print each warning only
	      the first time it occurs in the program; or error  to  raise  an
	      exception instead of printing a warning message.

	      The   full  form	of  argument  is  action:message:category:mod
	      ule:line.  Here, action is as explained above but  only  applies
	      to messages that match the remaining fields.  Empty fields match
	      all values; trailing empty fields may be omitted.   The  message
	      field  matches  the  start  of the warning message printed; this
	      match is case-insensitive.  The category field matches the warn
	      ing category.  This must be a class name; the match test whether
	      the actual warning category of the message is a subclass of  the
	      specified  warning category.  The full class name must be given.
	      The module field matches the (fully-qualified) module name; this
	      match  is  case-sensitive.  The line field matches the line num
	      ber, where zero matches all line numbers and is thus  equivalent
	      to an omitted line number.

       -x     Skip  the  first line of the source.  This is intended for a DOS
	      specific hack only.  Warning: the line numbers in error messages
	      will be off by one!

INTERPRETER INTERFACE
       The interpreter interface resembles that of the UNIX shell: when called
       with standard input connected to a tty device, it prompts for  commands
       and  executes  them  until an EOF is read; when called with a file name
       argument or with a file as standard input,  it  reads  and  executes  a
       script  from  that  file;  when called with -c command, it executes the
       Python statement(s) given as command.  Here command may contain	multi
       ple  statements	separated by newlines.	Leading whitespace is signifi
       cant in Python statements!  In non-interactive mode, the  entire  input
       is parsed before it is executed.

       If  available,  the script name and additional arguments thereafter are
       passed to the script in the Python variable sys.argv , which is a  list
       of  strings (you must first import sys to be able to access it).  If no
       script name is given, sys.argv[0] is an empty string; if  -c  is  used,
       sys.argv[0] contains the string -c.  Note that options interpreted by
       the Python interpreter itself are not placed in sys.argv.

       In interactive mode, the primary prompt is  >>>;  the  second  prompt
       (which  appears	when a command is not complete) is ....  The prompts
       can be changed by assignment to sys.ps1 or  sys.ps2.   The  interpreter
       quits  when  it	reads an EOF at a prompt.  When an unhandled exception
       occurs, a stack trace is printed and control  returns  to  the  primary
       prompt;	in  non-interactive mode, the interpreter exits after printing
       the stack trace.  The interrupt	signal	raises	the  KeyboardInterrupt
       exception;  other  UNIX	signals are not caught (except that SIGPIPE is
       sometimes ignored, in favor of the IOError exception).  Error  messages
       are written to stderr.

FILES AND DIRECTORIES
       These are subject to difference depending on local installation conven
       tions; ${prefix}  and  ${exec_prefix}  are  installation-dependent  and
       should  be  interpreted	as for GNU software; they may be the same.  On
       Debian GNU/{Hurd,Linux} the default for both is /usr.

       ${exec_prefix}/bin/python
	      Recommended location of the interpreter.

       ${prefix}/lib/python
       ${exec_prefix}/lib/python
	      Recommended locations of the directories containing the standard
	      modules.

       ${prefix}/include/python
       ${exec_prefix}/include/python
	      Recommended  locations of the directories containing the include
	      files needed for developing Python extensions and embedding  the
	      interpreter.

       ~/.pythonrc.py
	      User-specific initialization file loaded by the user module; not
	      used by default or by most applications.

ENVIRONMENT VARIABLES
       PYTHONHOME
	      Change the  location  of	the  standard  Python  libraries.   By
	      default, the libraries are searched in ${prefix}/lib/python and  ${exec_prefix}/lib/python,  where  ${prefix}
	      and  ${exec_prefix} are installation-dependent directories, both
	      defaulting to /usr/local.  When $PYTHONHOME is set to  a	single
	      directory, its value replaces both ${prefix} and ${exec_prefix}.
	      To specify different values for these, set $PYTHONHOME to ${pre
	      fix}:${exec_prefix}.

       PYTHONPATH
	      Augments	the  default search path for module files.  The format
	      is the  same  as	the  shells  $PATH:  one  or  more  directory
	      pathnames  separated  by	colons.   Non-existent directories are
	      silently ignored.   The  default	search	path  is  installation
	      dependent,  but  generally begins with ${prefix}/lib/python (see PYTHONHOME above).  The default search path is always
	      appended	to  $PYTHONPATH.   If  a script argument is given, the
	      directory containing the script is inserted in the path in front
	      of  $PYTHONPATH.	The search path can be manipulated from within
	      a Python program as the variable sys.path .

       PYTHONSTARTUP
	      If this is the name of a readable file, the Python  commands  in
	      that  file  are executed before the first prompt is displayed in
	      interactive mode.  The file is executed in the same  name  space
	      where  interactive commands are executed so that objects defined
	      or imported in it can  be  used  without	qualification  in  the
	      interactive  session.   You  can also change the prompts sys.ps1
	      and sys.ps2 in this file.

       PYTHONY2K
	      Set this to a non-empty string  to  cause  the  time  module  to
	      require  dates  specified  as  strings to include 4-digit years,
	      otherwise 2-digit years are converted based on  rules  described
	      in the time module documentation.

       PYTHONOPTIMIZE
	      If  this is set to a non-empty string it is equivalent to speci
	      fying the -O option. If set to an integer, it is	equivalent  to
	      specifying -O multiple times.

       PYTHONDEBUG
	      If  this is set to a non-empty string it is equivalent to speci
	      fying the -d option. If set to an integer, it is	equivalent  to
	      specifying -d multiple times.

       PYTHONINSPECT
	      If  this is set to a non-empty string it is equivalent to speci
	      fying the -i option.

       PYTHONUNBUFFERED
	      If this is set to a non-empty string it is equivalent to	speci
	      fying the -u option.

       PYTHONVERBOSE
	      If  this is set to a non-empty string it is equivalent to speci
	      fying the -v option. If set to an integer, it is	equivalent  to
	      specifying -v multiple times.

AUTHOR
       The Python Software Foundation: http://www.python.org/psf

INTERNET RESOURCES
       Main website:  http://www.python.org/
       Documentation:  http://docs.python.org/
       Community website:  http://starship.python.net/
       Developer resources:  http://www.python.org/dev/
       FTP:  ftp://ftp.python.org/pub/python/
       Module repository:  http://www.vex.net/parnassus/
       Newsgroups:  comp.lang.python, comp.lang.python.announce

LICENSING
       Python  is  distributed	under  an  Open  Source license.  See the file
       "LICENSE" in the Python source distribution for information on terms  &
       conditions  for	accessing  and	otherwise  using Python and for a DIS
       CLAIMER OF ALL WARRANTIES.



	     $Date: 2005-03-21 01:18:04 +1100 (Mon, 21 Mar 2005) $   PYTHON(1)




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