On 31/08/2023 19:31, Eric Blake wrote:
POSIX Issue 8 will be obsoleting %b (escape sequence interpolation) so that future Issue 9 can change to having %b (binary literal output) that aligns with C2x. But since escape interpolation may still remain useful, POSIX suggested %#s (which is undefined in all versions of C) as a possible alias for the older %b behavior.* src/printf.c (print_formatted, usage): Support %#s as an alias for %b, in order to open doors to future repurposing of %b to binary output while still allowing access to its old behavior. * doc/coreutils.texi (printf invocation): Document it. * NEWS: Likewise. * tests/printf/printf-quote.sh: Add unit test coverage.
Patch looks good thanks. I'd add in the attached test addition. As for compat, I notice that existing coreutils will reject %#s, while bash 5.2.15, ksh 1.0.4, dash 0.5.12 will treat as %s. cheers, Pádraig
diff --git a/tests/printf/printf.sh b/tests/printf/printf.sh index 834012cc5..0c0948c6c 100755 --- a/tests/printf/printf.sh +++ b/tests/printf/printf.sh @@ -64,6 +64,8 @@ $prog '6 \41\n' | tr '\41' '!' >> out # prints a NUL byte followed by the digit '2' and a 'y'. $prog '7 \2y \02y \002y \0002y\n' |tr '\0\2' '*=' >> out +$prog '8 %#s %#s %#s %#s\n' '\1y' '\01y' '\001y' '\0001y'|tr '\1' = >> out +# Deprecated %b equivalent $prog '8 %b %b %b %b\n' '\1y' '\01y' '\001y' '\0001y'|tr '\1' = >> out $prog '9 %*dx\n' -2 0 >>out || fail=1 @@ -90,6 +92,7 @@ cat <<\EOF > exp 6 ! 7 =y =y =y *2y 8 =y =y =y =y +8 =y =y =y =y 9 0 x 10 0x 11 x
