Use python to customize interactive command lines

This article mainly introduces how to customize interactive command lines in python. you can refer to the Python interactive command line to configure it through the startup file.

When Python is started, it looks for the environment variable PYTHONSTARTUP and executes the program code in the specified file in the variable. The specified file name and address can be arbitrary. When you press the Tab key, the content and command history are automatically supplemented. This effectively enhances the command line, and these tools are implemented based on the readline module (which requires the aid of the readline library ).

Here is an example of a simple startup script file. It adds the key auto-completion content and history command functions to the python command line.

[python@python ~]$ cat .pythonstartupimport readlineimport rlcompleterimport atexitimport os#tab completionreadline.parse_and_bind('tab: complete')#history filehistfile = os.path.join(os.environ['HOME'], '.pythonhistory')try:  readline.read_history_file(histfile)except IOError:  passatexit.register(readline.write_history_file,histfile)del os,histfile,readline,rlcompleter

Set environment variables

[python@python ~]$ cat .bash_profile|grep PYTHONexport PYTHONSTARTUP=/home/python/.pythonstartup

Verify the Tab key completion and View History commands.

[python@python ~]$ pythonPython 2.7.5 (default, Oct 6 2013, 10:45:13)[GCC 4.1.2 20080704 (Red Hat 4.1.2-44)] on linux2Type "help", "copyright", "credits" or "license" for more information.>>> import md5>>> md5.md5.__class__(     md5.__getattribute__( md5.__reduce__(    md5.__subclasshook__(md5.__delattr__(    md5.__hash__(     md5.__reduce_ex__(   md5.blocksizemd5.__dict__      md5.__init__(     md5.__repr__(     md5.digest_sizemd5.__doc__      md5.__name__      md5.__setattr__(    md5.md5(md5.__file__      md5.__new__(      md5.__sizeof__(    md5.new(md5.__format__(    md5.__package__    md5.__str__(      md5.warnings>>> import os>>> import md5

Note: if the following occurs during make:

Python build finished, but the necessary bits to build these modules were not found:_tkinter            gdbm      readline      sunaudiodev

If this is ignored, import readline reports an error. No module is specified!

The specified package is missing:

redhat:   readline-devel.xxx.rpm

Install and re-compile and execute, the problem can be solved.