Character function



This function are defined in the Header file Ctype.h returns true if the given character is a digit

  • int isalnum(int c);

    The function returns nonzero if c is alphanumeric

  • int isalpha(int c);

    The function returns nonzero if c is alphabetic only

  • int isdigit(int c);

    The function returns nonzero if c is a numeric digit

  • int islower(int c);

    The function returns nonzero if c is a lower case character.

  • int isspace(int c);

    The function returns nonzero if c is space character

  • int isupper(int c);

    The function returns nonzero if c is upper case character

  • int tolower(int c);

    The function returns the corresponding lowercase letter if one exists and if isupper(c); otherwise, it returns c.

  • int toupper(int c);

    The function returns the corresponding uppercase letter if one exists and if islower(c); otherwise, it returns c.