Function pwrite 

#[unsafe(no_mangle)]
pub unsafe extern "C" fn pwrite(
    fildes: c_int,
    buf: *const c_void,
    nbyte: size_t,
    offset: off_t,
) -> ssize_t

See https://pubs.opengroup.org/onlinepubs/9799919799/functions/write.html.

Equivalent to write(), except that it writes into a given position and does not change the file offset (regardless of whether O_APPEND is set).

When successful, returns a non-negative number indicating the number of bytes actually written to the file associated with fildes. Upon failure, returns -1.