* lib/human.c, lib/human.h (human_readable): Coalesce last two args into one, for convenience. All callers changed. (human_block_size): New function. * lib/human.c: Include <config.h> only if HAVE_CONFIG_H. Include <stdlib.h> if HAVE_STDLIB_H; declare getenv unless HAVE_DECL_GETENV. (_): New macro. Include <argmatch.h>, <error.h>, <xstrtoul.h>. (DEFAULT_BLOCK_SIZE): New macro. (block_size_args, block_size_types): New constants. (humblock): New function.