/bin/true (was [TUHS] basic tools / Universal Unix)
dave at horsfall.org
Fri Oct 20 07:43:23 AEST 2017
On Thu, 19 Oct 2017, Ron Natalie wrote:
> My favorite reduction to absurdity was /bin/true. Someone decided we
> needed shell commands for true and false. Easy enough to add a script
> that said "exit 0" or exit 1" as its only line. Then someone realized
> that the "exit 0" in /bin true was superfluous, the default return was
> 0. /bin/true turned into an empty, yet executable, file.
> Then the lawyers got involved. We got a version of a packaged UNIX (I
> think it was Interactive Systems). Every shell script got twelve lines
> of copyright/license boilerplate. Including /bin true. The file had
> nothing but useless comment in it.
I've also seen /bin/true and /bin/false (I've often been tempted to write
"/bin/maybe" to introduce a little non-determinism) as *separate binaries*
i.e. not even linked.
These days they appear to be built-ins (as I would expect).
Dave Horsfall DTM (VK2KFU) "Those who don't understand security will suffer."
More information about the TUHS