| .TH PYTHON "1" "5 September, 2000" |
| .SH NAME |
| python \- an interpreted, interactive, object-oriented programming language |
| .SH SYNOPSIS |
| .B python |
| [ |
| .B \-d |
| ] |
| [ |
| .B \-i |
| ] |
| [ |
| .B \-O |
| ] |
| [ |
| .B \-S |
| ] |
| [ |
| .B \-t |
| ] |
| [ |
| .B \-u |
| ] |
| [ |
| .B \-v |
| ] |
| [ |
| .B \-x |
| ] |
| [ |
| .B \-h |
| ] |
| [ |
| .B \-V |
| ] |
| .br |
| [ |
| .B \-c |
| .I command |
| | |
| .I script |
| | |
| \- |
| ] |
| [ |
| .I arguments |
| ] |
| .SH DESCRIPTION |
| Python is an interpreted, interactive, object-oriented programming |
| language 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 (perhaps too) much detail. |
| (These documents may be located via the |
| .B "INTERNET RESOURCES" |
| below; they may be installed on your system as well.) |
| .PP |
| Python's 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 |
| applications. |
| See the internal documentation for hints. |
| .SH COMMAND LINE OPTIONS |
| .TP |
| .B \-d |
| Turn on parser debugging output (for wizards only, depending on |
| compilation options). |
| .TP |
| .B \-i |
| When a script is passed as first argument or the \fB\-c\fP 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. |
| .TP |
| .B \-O |
| Turn on basic optimizations. This changes the filename extension for |
| compiled (bytecode) files from |
| .I .pyc |
| to \fI.pyo\fP. Given twice, causes docstrings to be discarded. |
| .TP |
| .B \-S |
| Disable the import of the module |
| .I site |
| and the site-dependent manipulations of |
| .I sys.path |
| that it entails. |
| .TP |
| .B \-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. |
| .TP |
| .B \-u |
| Force stdin, stdout and stderr to be totally unbuffered. |
| .TP |
| .B \-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. |
| .TP |
| .B \-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! |
| .TP |
| .B \-h |
| Prints the usage for the interpreter executable and exits. |
| .TP |
| .B \-V |
| Prints the Python version number of the executable and exits. |
| .TP |
| .BI "\-c " command |
| Specify the command to execute (see next section). |
| This terminates the option list (following options are passed as |
| arguments to the command). |
| .SH 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 |
| .I script |
| from that file; |
| when called with |
| .B \-c |
| .I command, |
| it executes the Python statement(s) given as |
| .I command. |
| Here |
| .I command |
| may contain multiple statements separated by newlines. |
| Leading whitespace is significant in Python statements! |
| In non-interactive mode, the entire input is parsed befored it is |
| executed. |
| .PP |
| If available, the script name and additional arguments thereafter are |
| passed to the script in the Python variable |
| .I sys.argv , |
| which is a list of strings (you must first |
| .I import sys |
| to be able to access it). |
| If no script name is given, |
| .I sys.argv[0] |
| is an empty string; if |
| .B \-c |
| is used, |
| .I sys.argv[0] |
| contains the string |
| .I '-c'. |
| Note that options interpreted by the Python interpreter itself |
| are not placed in |
| .I sys.argv. |
| .PP |
| 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 |
| .I sys.ps1 |
| or |
| .I 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 |
| .I Keyboard\%Interrupt |
| exception; other UNIX signals are not caught (except that SIGPIPE is |
| sometimes ignored, in favor of the |
| .I IOError |
| exception). Error messages are written to stderr. |
| .SH FILES AND DIRECTORIES |
| These are subject to difference depending on local installation |
| conventions; ${prefix} and ${exec_prefix} are installation-dependent |
| and should be interpreted as for GNU software; they may be the same. |
| The default for both is \fI/usr/local\fP. |
| .IP \fI${exec_prefix}/bin/python\fP |
| Recommended location of the interpreter. |
| .PP |
| .I ${prefix}/lib/python<version> |
| .br |
| .I ${exec_prefix}/lib/python<version> |
| .RS |
| Recommended locations of the directories containing the standard |
| modules. |
| .RE |
| .PP |
| .I ${prefix}/include/python<version> |
| .br |
| .I ${exec_prefix}/include/python<version> |
| .RS |
| Recommended locations of the directories containing the include files |
| needed for developing Python extensions and embedding the |
| interpreter. |
| .RE |
| .IP \fI~/.pythonrc.py\fP |
| User-specific initialization file loaded by the \fIuser\fP module; |
| not used by default or by most applications. |
| .SH ENVIRONMENT VARIABLES |
| .IP PYTHONHOME |
| Change the location of the standard Python libraries. By default, the |
| libraries are searched in ${prefix}/lib/python<version> and |
| ${exec_prefix}/lib/python<version>, where ${prefix} and ${exec_prefix} |
| are installation-dependent directories, both defaulting to |
| \fI/usr/local\fP. 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 ${prefix}:${exec_prefix}. |
| .IP PYTHONPATH |
| Augments the default search path for module files. |
| The format is the same as the shell's $PATH: one or more directory |
| pathnames separated by colons. |
| Non-existant directories are silently ignored. |
| The default search path is installation dependent, but generally |
| begins with ${prefix}/lib/python<version> (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 |
| .I sys.path . |
| .IP 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 |
| .I sys.ps1 |
| and |
| .I sys.ps2 |
| in this file. |
| .IP PYTHONDEBUG |
| If this is set to a non-empty string it is equivalent to specifying |
| the \fB\-d\fP option. |
| .IP PYTHONINSPECT |
| If this is set to a non-empty string it is equivalent to specifying |
| the \fB\-i\fP option. |
| .IP PYTHONUNBUFFERED |
| If this is set to a non-empty string it is equivalent to specifying |
| the \fB\-u\fP option. |
| .IP PYTHONVERBOSE |
| If this is set to a non-empty string it is equivalent to specifying |
| the \fB\-v\fP option. |
| .SH AUTHOR |
| .nf |
| Guido van Rossum |
| BeOpen.com |
| 160 Saratoga Avenue |
| Santa Clara, CA 95051 |
| USA |
| .PP |
| E-mail: guido@beopen.com, guido@python.org |
| .fi |
| .PP |
| And a cast of thousands. |
| .SH INTERNET RESOURCES |
| Main website: http://www.python.org |
| .br |
| BeOpen development team: http://pythonlabs.com |
| .br |
| Community website: http://starship.python.net |
| .br |
| Developer resources: |
| .br |
| http://sourceforge.net/project/?group_id=5470 |
| .br |
| FTP: ftp://ftp.python.org/pub/python |
| .br |
| Module repository: http://www.vex.net/parnassus/ |
| .br |
| Newsgroups: comp.lang.python, comp.lang.python.announce |
| .SH 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 |
| DISCLAIMER OF ALL WARRANTIES. |