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ctype.h 437B

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  1. #ifndef _CTYPE_H
  2. #define _CTYPE_H
  3. /** @file
  4. *
  5. * Character types
  6. */
  7. #define isdigit(c) ((c) >= '0' && (c) <= '9')
  8. #define islower(c) ((c) >= 'a' && (c) <= 'z')
  9. #define isupper(c) ((c) >= 'A' && (c) <= 'Z')
  10. static inline unsigned char tolower(unsigned char c)
  11. {
  12. if (isupper(c))
  13. c -= 'A'-'a';
  14. return c;
  15. }
  16. static inline unsigned char toupper(unsigned char c)
  17. {
  18. if (islower(c))
  19. c -= 'a'-'A';
  20. return c;
  21. }
  22. #endif /* _CTYPE_H */