The ****`wcstoumax` function**** converts a wide string to an `unsigned integer`. `wchar` is the pointer that points to the string that is to be converted. 
> Wide string is the one that contains characters larger than 8 bits. 

The `wchar.h` header needs to be included to use this function as shown below:
```C
#include <wchar.h>
```

# Prototype
The function prototype is as follows:
```C
uintmax_t wcstoumax(const wchar* widestr, wchar** endPtr, int base);
```

# Parameters
The function takes the following parameters:

**`widestr`** - a pointer type that points to wide string.

**`endPtr`** - a pointer type that provides reference to object of type `wchar`. This can be null if it is not used.

**`base`** - an integer that specifies the base of the integer value to be converted.

The conversion is invalid when the return value falls out of range. For example, the range for `base` is {0, 1, 2, ..., 36}. 

# Example
The following code shows the use of the `wcstoumax` function for different values of `widestr` and `base`:

#include <inttypes.h>
#include <stdio.h>
#include <string.h> // for string
#include <wchar.h> // for wchar_t

 
int main(void)
{
  wchar_t* endptr;
 
  wprintf(L"Value 1 is %ld\n", wcstoumax(L"11111111", &endptr, 2));   // base 2                     
  wprintf(L"Value 2 is %ld\n", wcstoumax(L"1wer", &endptr, 2));       // base 2                     
  wprintf(L"Value 3 is %ld\n", wcstoumax(L" -123junk", &endptr, 10)); // base 10                    
  wprintf(L"Value 4 is %ld\n", wcstoumax(L"XyZ",&endptr, 36));       // base 36                    
}

What is wcstoumax in C ?

Prototype

Parameters

Return value

Example