POSIXLY_CORRECT is set and the first argument is not "-n", echo now
outputs all option-like arguments instead of treating them as options.
+ printf has several changes:
+
+ It now uses 'intmax_t' (not 'long int') to format integers, so it
+ can now format 64-bit integers on most modern hosts.
+
+ On modern hosts it now supports the C99-inspired %a, %A, %F conversion
+ specs, the "'" and "0" flags, and the ll, j, t, and z length modifiers
+ (this is compatible with recent Bash versions).
+
+ The printf command now rejects invalid conversion specifications
+ like %#d, instead of relying on undefined behavior in the underlying
+ printf function.
+
who now prints user names in full instead of truncating them after 8 bytes.
** New features