According to the man page, the second parameter is not of type
char *, but rather of type
void *. This emphasizes that it doesn't matter what type of data is used. All you need to do is specify the number of bytes correctly.
If you were sending an array of char (which you're not), the number of bytes would be the number of chars, since a character occupies one byte. If your array contains, say, 346 integers, the number of bytes you will be writing or reading is
Hope this helps.