if (*s == '=' && isxdigit (*(s+1)) && isxdigit (*(s+2)))
if (*s == '=' && isxdigit ((unsigned char) *(s+1)) && isxdigit ((unsigned char) *(s+2)))
static int qp_decode_triple (char *s, char *d){  /* soft line break */  if (*s == '=' && !(*(s+1)))    return 1;    /* quoted-printable triple */  if (*s == '=' && isxdigit (*(s+1)) && isxdigit (*(s+2)))  {    *d = (hexval (*(s+1)) << 4) | hexval (*(s+2));    return 0;  }    /* something else */  return -1;}