[Python-Dev] PEP 394 request for pronouncement (python2 symlink in *nix systems)

[Antoine Pitrou]

On Sun, 12 Feb 2012 19:04:30 +1000
Nick Coghlan <ncoghlan at gmail.com> wrote:
> PEP 394 [1] aims to document our collective recommendation for
> allowing shebang lines to specifically request some version of 2.x,
> without requiring that it be exactly 2.7 (or 2.6, etc).
> 
> I'd let this drift for a while, but the imminent release of 2.7.3
> makes it necessary to push for a final pronouncement. Kerrick has the
> necessary Makefile.pre.in patch up on the tracker [2] to add the hard
> link for the python2 name.

Why hard links? Symlinks are much more introspectable. When looking at
a hard link I have no easy way to know it's the same as whatever other
file in the same directory.

I also don't understand this mention:

“The make install command in the CPython 3.x series will similarly
install the python3.x, idle3.x, pydoc3.x, and python3.x-config binaries
(with appropriate x), and python3, idle3, pydoc3, and python3-config as
hard links. This feature will first appear in CPython 3.3.”

This feature actually exists in 3.2 (but with a symlink, fortunately):

$ ls -la  ~/opt/bin/pydoc3
lrwxrwxrwx 1 antoine antoine 8 oct.  15 21:24 /home/antoine/opt/bin/pydoc3 -> pydoc3.2*


Regards

Antoine.