#include <stdlib.h>

#include <locale.h>

#include <errno.h>

#include <stdio.h>

 

extern int errno;



/*

 * The following example uses the wcstod subroutine to convert

 * a wide character string to a signed long integer.

 */

int main(int argc, char **argv) {

    wchar_t   *pwcs, *endptr;

    long int  retval;

 

    setlocale(LC_ALL, "");

    

    /*

     * Let pwcs point to a wide character null terminated

     * string containing a signed long integer value.

     */

    errno = 0; /* set errno to  zero  */

    retval = wcstol(pwcs, &endptr, 0);

 

    if (errno != 0) { /* errno has changed, so error has occurred */

        if (errno == ERANGE) {

            /*  

             * Correct value is outside range of

             * representable values. Case of overflow

             * error

             */

             if ((retval == LONG_MAX) || (retval == LONG_MIN)) {

                /*  Error case. Handle accordingly.     */

             } else if(errno == EINVAL) {

                /*  The value of base is not supported  */

                /*  Handle appropriately                */

            }

        }

    }

    /*  retval contains the long integer. */

    printf("Double from wide-character: %l\n", retval);

    return (0);

}