std:: wcstok

Finds the next token in a null-terminated wide string pointed to by str . The separator characters are identified by null-terminated wide string pointed to by delim .

• If str ! = nullptr , the call is treated as the first call to std::wcstok for this particular wide string. The function searches for the first wide character which is not contained in delim .

• If no such wide character was found, there are no tokens in str at all, and the function returns a null pointer.
• If such wide character was found, it is the beginning of the token . The function then searches from that point on for the first wide character that is contained in delim .

• If no such wide character was found, str has only one token, and future calls to std::wcstok will return a null pointer.
• If such wide character was found, it is replaced by the null wide character L ' \0 ' and the parser state (typically a pointer to the following wide character) is stored in the user-provided location * ptr .

• The function then returns the pointer to the beginning of the token.

• If str == nullptr , the call is treated as a subsequent calls to std::wcstok : the function continues from where it left in previous invocation with the same * ptr . The behavior is the same as if the pointer to the wide character that follows the last detected token is passed as str .

Parameters

Return value

Pointer to the beginning of the next token or null pointer if there are no more tokens.

Note

This function is destructive: it writes the L ' \0 ' characters in the elements of the string str . In particular, a wide string literal cannot be used as the first argument of std::wcstok .

Unlike std::strtok , this function does not update static storage: it stores the parser state in the user-provided location.

Unlike most other tokenizers, the delimiters in std::wcstok can be different for each subsequent token, and can even depend on the contents of the previous tokens.

Example

#include <cwchar>
#include <iostream>
 
int main()
{
    wchar_t input[100] = L"A bird came down the walk";
    wchar_t* buffer;
    wchar_t* token = std::wcstok(input, L" ", &buffer);
    while (token)
    {
        std::wcout << token << '\n';
        token = std::wcstok(nullptr, L" ", &buffer);
    }
}

A
bird
came
down
the
walk

See also