Re: PATH question

[jeffd <fixedored@gmail.com>]

Tony Heal wrote:
> I have a problem on one of my servers. The ‘ls’ command does not have 
> the –h switch available. So as a workaround until I can determine what 
> caused this and why I wanted to use the ‘ls’ file from another server. 
> I copied /bin/ls from server # 2 onto server # 1 and tested it and it 
> works fine, including the –h switch.
>
> So I typed set, read the PATH and found that /usr/local/bin is in the 
> path before /usr/bin. I thought I could simply drop the new ls in 
> /usr/local/bin and the system would see it first when called and use 
> it. WRONG.
>
> So my questions are:
>
>    1. why not?
>    2. what is the order used in the path?
>
> Thanks
>
> Tony
You can use 'which' to find out which ls is being called, but it goes by 
first come first serve:
echo $PATH
/home/jeffd/bin:/usr/local/bin:/usr/bin:/bin
jeffd@proto:~$ touch ~/bin/ls
jeffd@proto:~$ chmod 755 ~/bin/ls
jeffd@proto:~$ which ls
/home/jeffd/bin/ls
jeffd@proto:~$ rm ~/bin/ls
jeffd@proto:~$ which ls
/bin/ls