问题
I'm wanting to use some newer software that requires Python 2.6, and we currently have both 2.4 and 2.6 installed on our dedicated CentOS server, which looks like this:
$ which python
/usr/local/bin/python
$ which python2.6
/usr/bin/python2.6
$ which python2.4
/usr/local/bin/python2.4
$ ls -l /usr/local/bin/py*
-rwxr-xr-x 1 root root 81 Aug 9 2007 /usr/local/bin/pydoc
-rwxr-xr-x 2 root root 3394082 Aug 9 2007 /usr/local/bin/python
-rwxr-xr-x 2 root root 3394082 Aug 9 2007 /usr/local/bin/python2.4
How can I switch it to start using 2.6 as the default python?
回答1:
As root:
ln -sf /usr/bin/python2.6 /usr/local/bin/python
This will make a symbolic link from /usr/local/bin/python --> /usr/bin/python2.6 (replacing the old hardlink).
回答2:
As an alternative, you can also just add an alias for the command "python" in the your bash shell's startup file.
so open the startup file: emacs ~/.bashrc
in the editor u append: alias "python" "python2.6"
and restart the shell.
回答3:
rm /usr/local/bin/python
ln -s /usr/local/bin/python2.6 /usr/local/bin/python
回答4:
Add an alias for the command "python" in the your bash shell's startup file. DON'T change a symbolic link from /usr/bin/python, because changing the default Python (in Ubuntu or Linux Mint for example) may break your system
P.S.: read other answers
回答5:
In CentOS
ln -sf /usr/local/bin/python2.6 /usr/local/bin/python
ln -sf /usr/local/bin/python2.6 /usr/bin/python
To check version do:
python -V
Then to fix yum "No module named yum", you should do:
vi `which yum`
and modify #!/usr/bin/python to #!/usr/bin/python2.4
回答6:
I had similar problem when using meld, I simply renamed the one under local and it worked. Not a good solution I know, but I can always take it back.
sudo mv /usr/local/bin/python /usr/local/bin/re_python
来源：https://stackoverflow.com/questions/3339530/change-default-python-version-from-2-4-to-2-6