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Proper shebang for python3


On 24Jul2019 22:57, Dan Sommers <2QdxY4RzWzUUiLuE at potatochowder.com> wrote:
>On 7/24/19 10:24 PM, Michael Torrie wrote:
>> ... In more recent times, binaries that are mostly applicable to the
>> super user go there.  I don't see why you would want to merge those.
>> A normal user rarely has need of much in /sbin.  Already /bin has way
>> too much stuff in it (although I don't see any other way to
>> practically do it without ridiculous PATHs searching all over the
>> disk).
>
>On ancient file systems (SysV?), ISTR something like 1400 files in a
>directory being some sort of limit, or perhaps a major performance
>issue.  Separate directories (including /usr/X11/bin) mitigated that,
>too.

I don't recall there being any specific hard limit though. What does 
happen in decent modern filesystems is that directories have a hash 
table in them for lookups, making a file name access constant time 
instead of a linear search.

Also, shells like zsh keep a hash table of the available commands to 
speed invocation, avoiding a linear $PATH search.

I don't recall stuff like /usr/X11/bin being aimed at performance (but I 
would not necessarily know); it has always seemed more like partitioning 
out various software groups - in this case the X11 Window System stuff.  
If nothing else, this makes separate development easier.

>> Having said that, I note that on my CentOS 7 workstation, sbin seems
>> to be in the path by default. So that negates my argument I suppose.
>> Although I might have made that change myself.
>
>My .shrc file has all sorts of leftovers from the old days, but my
>current Linux PATH is just $HOME/bin, $HOME/local/bin, and /usr/bin.

Hmm. 21 componetent in my $PATH here :-)

Cheers,
Cameron Simpson <cs at cskk.id.au>