I have installed python 2.7.3 on CentOS 6 with thse instructions
http://villaroad.com/2010/10/rolling-python-2-6-2-on-centos-5-3/
I have added aliases to bash_profile of both root and myuser for new python. Now when I write python to shell, it runs python2.7.3 correctly from both users.
However, if I write sudo python it stills runs old version python2.6.6
What could be the problem?
sudo doesn't use your shell to run commands, it just execs the command directly. This means (a) there's nothing that sources root's bash_profile, so it doesn't matter what you put there, and (b) shell aliases wouldn't matter even if they were set.
So, if you want to use aliases to specify a different python than the one that's on your PATH, you can't use sudo python to run that same one.
The easiest, and probably safest, fix is to be explicit: run sudo /path/to/other/python. If you need to do this often enough, you can always create an alias for that.
If you really want to, you can make sudo use a shell. Either explicitly generate the bash command line that runs python, or (more simply) just use the -s or -i flags. (In this case, if you're trying to get root's ~/.bash_profile run, -s won't do it, but -i will.) But sudoing shells is not as safe as sudoing programs. Your sudoers may even be explicitly configured to prevent you from doing it. (You can fix that with visudo if you want, but opening a security hole without understanding exactly what you're opening is generally considered a bad thing to do.)
sudo /path/to/other/python foo.py is sudo `which python` foo.py
$PATH, but not if it's an alias, and that's what the OP was asking about. I suppose you could use /usr/bin/which instead of the bash builtin; I believe the GNU tools version that comes with CentOS 6 has a --read-aliases flag or something like that, so you can do something like sudo $(alias | which --read-aliases python). (That's just off the top of my head; I don't have a machine to test on at the moment.)I would suggest using sudo -i when calling the script. Straight from man sudo:
-i [command]
The -i (simulate initial login) option runs the shell specified in the passwd(5) entry of the target user as a login shell. This means that login-specific resource files such as .profile or .login will be read by the shell. If a command is specified, it is passed to the shell for execution. Otherwise, an interactive shell is executed. sudo attempts to change to that user's home directory before running the shell. It also initializes the environment, leaving DISPLAY and TERM unchanged, setting HOME , MAIL , SHELL , USER , LOGNAME , and PATH , as well as the contents of /etc/environment on Linux and AIX systems. All other environment variables are removed.
The problem is that your $PATH is changing upon execution.
You can either use sudo -E:
-E The -E (preserve environment) option will override the env_reset option in sudoers(5)). It is only available when either the matching command has the SETENV tag or the setenv option is set in sudoers(5).
... or you can specify the full path to your executable. sudo `which python`.
(It looks like you used alias per the docs. This method would handle that too.)
-E doesn't help with aliases; you need to sudo a shell to get shell aliases (either explicitly, or via -s or -i).
which python" does handle it, though.The bin directory is probably referencing the old version of Python
> ls -la /usr/bin/python
lrwxrwxrwx 1 root root 9 Dec 21 2013 /usr/bin/python -> python2.7
Redirect the default python version to the one you want.
sudothrows away the PATH.