VMS Help TCPIP Services, Programming Interfaces, Sockets API, sendto()  *Conan The Librarian (sorry for the slow response - running on an old VAX)

    Sends bytes through a socket to any other socket.
    The $QIO equivalent is the IO$_WRITEVBLK function.
    Format
      #include  <types.h>
      #include  <socket.h>
      int sendto  ( int s, char *msg, int len, int flags, struct
                  sockaddr *to, int tolen );

  Additional Information (explode) :

• Arguments
• Description
• Return Values
• Errors