python中的tab键 python输出tab键

一、python添加TAB键

将以下代码保存到python库中，命名为 tab.

 

#vim tab.py     #编辑模块


#!/usr/local/bin/python
#python startup file

import sys
import readline
import rlcompleter
import atexit
import os

#tab completion
readline.parse_and_bind('tab:complete')
#history file
histfile = os.path.join(os.environ['HOME'],'.pythonhistory')
try:
  readline.read_history_file(histfile)
except IOError:
  pass
atexit.register(readline.write_history_file,histfile)

del os,histfile,readline,rlcompleter

 

#mv tab.py /usr/local/lib/python2.7/    #移动tab模块到python模块默认路径下

 

>>> import sys
>>> sys.path     #查看库默认存放路径
['', '/usr/local/lib/python2.7/site-packages/setuptools-0.6c11-py2.7.egg', '/usr/local/lib/python2.7/site-packages/readline-6.2.4.1-py2.7-linux-x86_64.egg', '/usr/local/lib/python27.zip', '/usr/local/lib/python2.7', '/usr/local/lib/python2.7/plat-linux2', '/usr/local/lib/python2.7/lib-tk', '/usr/local/lib/python2.7/lib-old', '/usr/local/lib/python2.7/lib-dynload', '/usr/local/lib/python2.7/site-packages']
>>> import tab    #导入TAB模块
>>> sys.
sys.__class__(              sys.exit(
sys.__delattr__(            sys.exitfunc(
sys.__dict__                sys.flags
sys.__displayhook__(        sys.float_info
sys.__doc__                 sys.float_repr_style
sys.__egginsert             sys.getcheckinterval(
sys.__excepthook__(         sys.getdefaultencoding(
sys.__format__(             sys.getdlopenflags(
sys.__getattribute__(       sys.getfilesystemencoding(
sys.__hash__(               sys.getprofile(
sys.__init__(               sys.getrecursionlimit(
sys.__name__                sys.getrefcount(
sys.__new__(                sys.getsizeof(

 

 

 

 二、新安装python2.7以上版本，导致Yum不能运行，找不到yum模块，因为yum是python程序写的。

执行yum报错信息：

# yum
There was a problem importing one of the Python modules
required to run yum. The error leading to this problem was:

   No module named yum     #找不到yum模块

Please install a package which provides this module, or
verify that the module is installed correctly.

It's possible that the above module doesn't match the
current version of Python, which is:
2.7.9 (default, Mar 11 2017, 19:17:43) 
[GCC 4.4.7 20120313 (Red Hat 4.4.7-17)]

If you cannot solve this problem yourself, please go to 
the yum faq at:
  http://yum.baseurl.org/wiki/Faq

编辑yum命令，修改头解释器为系统安装的python2.6版本。

查看python执行路径

# ll /usr/bin/py*
-rwxr-xr-x 2 root root 9032 Jan 22 2014 /usr/bin/python
lrwxrwxrwx. 1 root root    6 Mar 11 18:29 /usr/bin/python2 -> python
-rwxr-xr-x  2 root root 9032 Jan 22  2014 /usr/bin/python2.6
-rwxr-xr-x 2 root root 9032 Jan 22 2014 /usr/bin/python2.7

修改yum路径中python指向路径：

#vim /usr/bin/yum
#!/usr/bin/python #将此处改为python2.6路径(/usr/bin/python2.6)
import sys
try:
    import yum
except ImportError:
    print >> sys.stderr, """\
There was a problem importing one of the Python modules
required to run yum. The error leading to this problem was:

   %s

Please install a package which provides this module, or
verify that the module is installed correctly.

It's possible that the above module doesn't match the
current version of Python, which is:
%s

If you cannot solve this problem yourself, please go to 
the yum faq at:
  http://yum.baseurl.org/wiki/Faq
  
""" % (sys.exc_value, sys.version)
    sys.exit(1)

sys.path.insert(0, '/usr/share/yum-cli')
try:
    import yummain
    yummain.user_main(sys.argv[1:], exit_code=True)
except KeyboardInterrupt, e:
    print >> sys.stderr, "\n\nExiting on user cancel."
    sys.exit(1)