c - Expression must be a pointer to a complete object type when cast void pointer -

i'm trying function remove extension of name type wchar_t or char, inside for() cast void pointer type wchar_t or char, there error:

expression must pointer complete object type.

here sample code show instance of issue itself.

int removeextension(     void    *p_str,     /*  name                        */     bool    iswchar     /*  true：wchar_t, false：char　*/ ) {     int ii, len;      // length     len = (iswchar) ? wcslen( (wchar_t *)p_str ) : strlen( (char *)p_str );      // remove extension     /*　wchar_t　*/     if( iswchar ) {          for( ii = 0; ii < len; ii++ ) {             if( l'.' == (wchar_t *)p_str[ii] ) {  //error here                 (wchar_t *)p_str[ii] = l'\0';     //error here                 break;             }         }     }     /*　char　*/     else {          for( ii = 0; ii < len; ii++ ) {             if( '.' == (char *)p_str[ii]) {       //error here                 (char *)p_str[ii] = '\0';         //error here                 break;             }         }     }      return 0; } 

i'm not understanding error trying say. there no object or struct here.

i dont know why error, according this table expression

(wchar_t *)p_str[ii] (wchar_t *)(p_str[ii])

not ((wchar_t *)p_str)[ii],

probably it's not want