Symbolic Link insanity - python

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1

Ubuntu Support Template

Ubuntu Version:
Kubuntu 26.04

Desktop Environment (if applicable):
KDE Plasma

Problem Description:
Having recently installed upgraded to Kubuntu 26.04, I am bewildered that things I have known since I was a unix babe, my mother’s milk, so to speak, no longer appear valid. Specifically, that the which command tells you the location from which a command line will be run. And that symbolic links will be followed.

Consider the following sequence:

scohen@aigas:/usr/bin$ ll python*
lrwxrwxrwx 1 root root      19 Aug 19 10:15 python@ -> /usr/bin/python3.14
-rwxr-xr-x 1 root root     264 Nov 10  2025 python-argcomplete-check-easy-install-script*
lrwxrwxrwx 1 root root      10 Mar 21 02:46 python3@ -> python3.14
lrwxrwxrwx 1 root root      17 Mar 21 02:46 python3-config@ -> python3.14-config
-rwxr-xr-x 1 root root 8020928 Jun 19 05:46 python3.12*
lrwxrwxrwx 1 root root      34 Jun 19 05:46 python3.12-config@ -> x86_64-linux-gnu-python3.12-config
-rwxr-xr-x 1 root root 7481192 Jun 18 07:25 python3.14*
lrwxrwxrwx 1 root root      34 Jun 18 07:25 python3.14-config@ -> x86_64-linux-gnu-python3.14-config
scohen@aigas:/usr/bin$ which python
/usr/bin/python
scohen@aigas:/usr/bin$ python --version
Python 3.12.3
scohen@aigas:/usr/bin$ /usr/bin/python --version
Python 3.14.4

We see here that /usr/bin/python is a symbolic link to /usr/bin/python/3.14 and that which python returns /usr/bin/python as the executable to be run when python is typed.

However, executing python --version returns “Python 3.12.3” but
executing /usr/bin/python --version returns “Python 3.14.4”.

The only way I can make sense out of this is if something on my path ahead of
/usr/bin were pointing to another copy of python on my system.

But I looked at my path and no such python can be found in any of these path directories before the path gets to /usr/bin:

scohen@aigas:/usr/bin$ echo $PATH
/home/scohen/.local/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games:/snap/bin
scohen@aigas:/usr/bin$ find -L /home/scohen/.local/bin -type f -name python
scohen@aigas:/usr/bin$ find -L /usr/local/sbin -type f -name python
scohen@aigas:/usr/bin$ find -L /usr/local/bin -type f -name python
scohen@aigas:/usr/bin$ find -L /usr/sbin -type f -name python
scohen@aigas:/usr/bin$ find -L /usr/bin -type f -name python
find: File system loop detected; ‘/usr/bin/X11’ is part of the same file system loop as ‘/usr/bin’.
/usr/bin/python

So the python I expected to be launched (/usr/bin/python) is the first python along the path.

I don’t know what a “file system loop” is, but could that be the problem here?
It doesn’t seem to be, because the /usr/bin/X11/python points to the 3.14 version:

lrwxrwxrwx 1 root root 19 Aug 19 10:15 python@ -> /usr/bin/python3.14

I just want python to bring up the same version everywhere!

But the python command is somehow finding 3.12 and I don’t understand this.

UPDATE: fixed a command line that I had not copied correctly initially. However, the entire thrust of the question remains the same.

Relevant System Information:
nothing pops out at me. This is pure linux question.

Screenshots or Error Messages:

What I’ve Tried:
Tried this. It does not bring me anything that would be on the path before /usr/bin:

scohen@aigas:/usr/bin$ find / -type l -lname "/usr/bin/python3.12" 2>/dev/null
/home/scohen/python/gmail/venv/bin/python
/home/scohen/python/bookmarks-converter/venv/bin/python3.12
/home/scohen/.local/share/SASpro/runtime.old/py312/venv/bin/python3.12

Before Posting:

2

What do the following commands reveal?

$ which -a python 

and just for kicks

$ strace -q -efile python --version
3 
$ alias python3=gcc
$ python3 --version
gcc (Ubuntu 13.3.0-6ubuntu2~24.04.1) 13.3.0
Copyright (C) 2023 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

$ /usr/bin/python3 --version
Python 3.12.3
$
4 
scohen@aigas:/usr/bin$ which -a python
/usr/bin/python
/bin/python
scohen@aigas:/usr/bin$ /usr/bin/python version

scohen@aigas:/usr/bin$ /usr/bin/python --version
Python 3.14.4
scohen@aigas:/usr/bin$ /bin/python --version
Python 3.14.4
scohen@aigas:/usr/bin$ ll /bin/python
lrwxrwxrwx 1 root root 19 Aug 19 10:15 /bin/python@ -> /usr/bin/python3.14
scohen@aigas:/usr/bin$ ll /usr/bin/python
lrwxrwxrwx 1 root root 19 Aug 19 10:15 /usr/bin/python@ -> /usr/bin/python3.14

Both point to the same place which makes sense since /bin/python is just a symbolic link to /usr/bin/python3.14, as is /usr/bin/python

So nothing odd there, I don’t think.

Your other suggestion may point to something, but I’m not sure what:

scohen@aigas:/usr/bin$ strace -q -efile python --version
execve("/usr/bin/python", ["python", "--version"], 0x7fff67d045a8 /* 79 vars */) = 0
access("/etc/ld.so.preload", R_OK)      = -1 ENOENT (No such file or directory)
openat(AT_FDCWD, "/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
openat(AT_FDCWD, "/usr/lib/x86_64-linux-gnu/libm.so.6", O_RDONLY|O_CLOEXEC) = 3
openat(AT_FDCWD, "/usr/lib/x86_64-linux-gnu/libz.so.1", O_RDONLY|O_CLOEXEC) = 3
openat(AT_FDCWD, "/usr/lib/x86_64-linux-gnu/libexpat.so.1", O_RDONLY|O_CLOEXEC) = 3
openat(AT_FDCWD, "/usr/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
open("/proc/sys/vm/overcommit_memory", O_RDONLY) = 3
openat(AT_FDCWD, "/usr/lib/locale/locale-archive", O_RDONLY|O_CLOEXEC) = 3
openat(AT_FDCWD, "/usr/lib/x86_64-linux-gnu/gconv/gconv-modules.cache", O_RDONLY|O_CLOEXEC) = 3
Python 3.14.4
+++ exited with 0 +++

It does produce the correct version number, unlike python --version.

5

That’s doesn’t make any sense. What happens if you uninstall the python-is-python3 package and run those commands?

6

gpmitch

1h

That’s doesn’t make any sense. What happens if you uninstall the python-is-python3 package and run those commands?

scohen@aigas:/usr/bin$ sudo apt remove python-is-python3
[sudo: authenticate] Password:        
Package 'python-is-python3' is not installed, so not removed
7

@gpmitch
Your suggestion of removing python-is-python3 gave me an idea. I installed it since it wasn’t installed already. That made no difference. I removed it. The apt remove command also instructed me to do sudo apt autoremove which removed a whole boatload of stuff. Remember, I just did an upgrade from 24.04 to 26.04.

Anyway, after all these actions, your strace command produced different results:


scohen@aigas:/usr/bin$ strace -q -efile python --version
strace: Cannot find executable 'python'

And yet:

scohen@aigas:/usr/bin$ python --version
Python 3.12.3
8

That only leaves @avb66 suggestion that you’ve set a shell alias for python pointing to the 3.12 version.

9

gpmitch

43m

That only leaves @avb66 suggestion that you’ve set a shell alias for python pointing to the 3.12 version.

Is THAT what @avb66 was suggesting? I couldn’t make head or tail of it. Why was he aliasing python to gcc? I thought he was a madman. But he was demonstrating how it could happen.

That was a brilliant suggestion, @abv66. Thanks! I did have that alias. Removing it solved the problem. Weird. I didn’t have python-is-python3 installed but it seems to have been replaced by that alias in .bash_aliases. Was that a thing once?

10

Thanks, @abv66. You nailed it even if I didn’t understand why the heck you were aliasing python to gcc. That alias was in my .bash_aliases file.

Was that a thing at some point in the past: don’t install python-is-python3 but instead use aliases?

11

You apparently had setup Python venv in the past and probably setup an alias for it.