[TUHS] history of sbin?

[Warner Losh]

On Jan 31, 2013, at 6:28 PM, Random832 wrote:

> On 1/31/2013 7:06 PM, Jeremy C. Reed wrote:
>> I have heard the story a few times about sbin split is due to disk
>> space, such as told at
>> http://www.osnews.com/story/25556/Understanding_the_bin_sbin_usr_bin_usr_sbin_Split/
>> http://lists.busybox.net/pipermail/busybox/2010-December/074114.html
>> 
> Well, keeping in mind the stuff in /sbin used to be in /etc, in e.g. v7 - it's possible the real reason is simply they wanted binaries out of /etc and didn't want to put them in /bin where normal users might wonder "what is this?".

The split was for /usr and slash. Those things in / were local on small disks needed to boot the system just enough to mount a shared /usr remotely or to do some very limited recovery. This is why there's both /usr/bin and /bin.

It doesn't explain the /sbin and /bin split though.

I recall from SunOS 3.x documentation that I no longer have access to that the split was done to improve exec times for normal users. They didn't want the hash list to get too long with all the extra stuff in /sbin and /usr/sbin. the movement of the files from /etc also included movement to /libexec or /usr/libexec for many of the daemons that started out life in /etc. things like ifconfig moved to /sbin where people could more easily run them.  Maybe the original /etc and /bin split was for PATH reasons?

Warner