[PATCH] scripts/check-local-headers.sh: Verify there is input (don't hang).

[Joseph Myers]

On Wed, 10 Dec 2014, Carlos O'Donell wrote:

> If you have a failed build, and run `make check` it could hang forever
> in check-local-headers.sh because the awk script waits reading stdin
> if the input shell glob expands to nothing (missing input).
> 
> We have three options, close stdin, more awk to detect missing input
> or more shell. I chose the latter, but we could probably fix this with
> `exec 0>&-` in the shell if anyone objects to using find/grep or more
> awk.

We have consensus to redirect test input from /dev/null (unless a test 
needs input from some other file, of course).  See bug 14753.

-- 
Joseph S. Myers
joseph@codesourcery.com