isblank          3592 compat/regex/regcomp.c     BUILD_CHARCLASS_LOOP (isblank);
isblank            61 compat/regex/regex_internal.h #if !defined _LIBC && !defined HAVE_ISBLANK && !defined isblank
isblank            31 wildmatch.c    #ifdef isblank
isblank            32 wildmatch.c    # define ISBLANK(c) (ISASCII(c) && isblank(c))