Writes into a given position within a file without changing the
    file pointer.

    This function is supported on OpenVMS Integrity servers and
    Alpha only.

    Format

      #include  <unistd.h>

      ssize_t pwrite  (int file_desc, const void *buffer, size_t
                      nbytes, off_t offset);

  Additional Information (explode) :

• Arguments
• Description
• Return Values