Searches a string for the occurrence of one of a specified set of
    characters.

    Format

      #include  <string.h>

      char *strpbrk  (const char *str, const char *charset);

1 - Function Variants

    The strpbrk function has variants named _strpbrk32 and _strpbrk64
    for use with 32-bit and 64-bit pointer sizes, respectively.

2 - Arguments

 str

    A pointer to a character string. If this character string is a
    null string, 0 is returned.

 charset

    A pointer to a character string containing the set of characters
    for which the function will search.

3 - Description

    The strpbrk function scans the characters in the string, stops
    when it encounters a character found in charset, and returns the
    address of the first character in the string that appears in the
    character set.

4 - Return Values

    x                  The address of the first character in the
                       string that is in the set.
    NULL               Indicates that no character is in the set.