Re: [Valgrind-developers] Valgrind: r15765 - /trunk/none/tests/res_search.vgtest

[Mark W. <mj...@re...>]

On Wed, 2016-02-03 at 20:52 +0100, Petar Jovanovic wrote:
> On Thu, Jan 21, 2016 at 12:15 AM, <sv...@va...> wrote:
> > "command -v" is a (POSIX) shell builtin that should work everywhere.
> > "which" might be an external command that might not be installed in
> > which case the shell might just error out.
> >
> This will not work on systems that do not have 'host' installed, as
> vg_regtest script uses '/bin/sh -c' to execute the command, so it will
> return error code 127 and stop the testing. E.g. if I rename "host" to
> "host123" and try it out:
> 
> $ /bin/sh -c which host123 && host123
> $ echo $?
> 1
> $ /bin/sh -c command -v host123 && host123
> host123: command not found
> $ echo $?
> 127

O, that is annoying. Sorry about that.
So we don't want to use which because that is an external command that
might not be installed (which is how I found out) and we also want to
explicitly test that the host command actually is installed and that it
can resolve the given hostname (in case the build is running on a
networkless host).

Would the following work?

prereq: test $(command -v host) && host www.yahoo.com > /dev/null

It assumes test is always available, but I hope it is.