регулярные выражения в C 0

Quote from «man scanf»

[     Matches a nonempty sequence of characters from the specified set of
           accepted characters; the next pointer must be a pointer to char,
           and there must be enough room for all the characters in the string,
           plus a terminating NUL character.  The usual skip of leading white
           space is suppressed.  The string is to be made up of characters in
           (or not in) a particular set; the set is defined by the characters
           between the open bracket [ character and a close bracket ] charac-
           ter.  The set excludes those characters if the first character
           after the open bracket is a circumflex ^.  To include a close
           bracket in the set, make it the first character after the open
           bracket or the circumflex; any other position will end the set.
           The hyphen character - is also special; when placed between two
           other characters, it adds all intervening characters to the set.
           To include a hyphen, make it the last character before the final
           close bracket.  For instance, `[^]0-9-]' means the set ``everything
           except close bracket, zero through nine, and hyphen''.  The string
           ends with the appearance of a character not in the (or, with a cir-
           cumflex, in) set or when the field width runs out.
           If an l qualifier is present, the next pointer must be a pointer to
           wchar_t, into which the input will be placed after conversion by
           mbrtowc(3).

я все эти штучки, выяснял в info libc