[X-Unix] /bin strange directory ??

[William H. Magill]

On 23 May, 2005, at 21:20, David Gilden wrote:

> also I see two listing for zsh, what is the difference.

Use the long form of ls ... "ls -il /bin/zsh*

3071 -rwxr-xr-x    2 root  wheel     491340 Mar 20 18:39 zsh
3071 -rwxr-xr-x    2 root  wheel     491340 Mar 20 18:39 zsh-4.2.3

The first number is the inode, indicating that they are in fact  
identical.

This is a common System Administrator convention use to track  
versions ...

"zsh" is a hard link (not a symbolic link) to the "current installed  
version" of zsh, which in this case is version 4.1.1

This way one can quickly "upgrade" or change versions (or keep  
multiple versions around) by simply pointing the link at the  
appropriate version.

It allows one to write scripts utilizing a "generic" name for a  
program, while ensuring that you will always get the "latest version"  
-- assuming that the <pgm>-<version> scheme is used for the installed  
program.

T.T.F.N.
William H. Magill
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