tolower
#define tolower(x) (to_lower[x])
#define tolower(c) __sbtolower(c)
#undef tolower
tolower(int c)
tolower(int c)
#define tolower(c) ((c) + 0x20 * (((c) >= 'A') && ((c) <= 'Z')))
#define tolower(x) ((x >= 'A' && x <= 'Z')?(x+('a'-'A')):(x))