Am 03.07.2017 um 20:09 hat Eric Blake geschrieben:
> POSIX says that backslashes in the arguments to 'echo', as well as
> any use of 'echo -n' and 'echo -e', are non-portable; it recommends
> people should favor 'printf' instead. This is definitely true where
> we do not control which shell is running (such as in makefile snippets
> or in documentation examples). But even for scripts where we
> require bash (and therefore, where echo does what we want by default),
> it is still possible to use 'shopt -s xpg_echo' to change bash's
> behavior of echo. And setting a good example never hurts when we are
> not sure if a snippet will be copied from a bash-only script to a
> general shell script (although I don't change the use of non-portable
> \e for ESC when we know the running shell is bash).
>
> Replace 'echo -n "..."' with 'printf %s "..."', and 'echo -e "..."'
> with 'printf %b "...\n"', with the optimization that the %s/%b
> argument can be omitted if the string being printed is a strict
> literal with no '%', '$', or '`' (we could technically also make
> this optimization when there are $ or `` substitutions but where
> we can prove their results will not be problematic, but proving
> that such substitutions are safe makes the patch less trivial
> compared to just being consistent).
>
> In the qemu-iotests check script, fix unusual shell quoting
> that would result in word-splitting if 'date' outputs a space.
>
> In test 051, take an opportunity to shorten the line.
>
> In test 068, get rid of a pointless second invocation of bash.
>
> CC: qemu-triv...@nongnu.org
> Signed-off-by: Eric Blake <ebl...@redhat.com>
> diff --git a/tests/multiboot/run_test.sh b/tests/multiboot/run_test.sh
> index 78d7edf..c8f3da8 100755
> --- a/tests/multiboot/run_test.sh
> +++ b/tests/multiboot/run_test.sh
> @@ -26,7 +26,7 @@ run_qemu() {
> local kernel=$1
> shift
>
> - echo -e "\n\n=== Running test case: $kernel $@ ===\n" >> test.log
> + printf %b "\n\n=== Running test case: $kernel $@ ===\n\n" >> test.log
>
> $QEMU \
> -kernel $kernel \
Not completely sure why, but this broke the test with whitespace changes
like this:
-=== Running test case: mmap.elf -m 1.1M ===
+=== Running test case: mmap.elf -m1.1M ===
Kevin
