TCP/IP Programming Manual

Some of the following C header files are used internally by the NonStop TCP/IP, Parallel Library
TCP/IP, and NonStop TCP/IPv6 subsystems; others are useful in some application programs. The
files are user-readable and contain comments describing their contents, as follows:
udpvar.htcpseq.hsockvar.hnameser.hinsystm.haf.h
uio.htcptimr.hsyscal.hnetisr.hinvar.hdomain.h
user.htcpvar.htcp.hparam.hip.hicmpvar.h
time.htcpdeb.hprotosw.hipicmp.hifarp.h
types.htcpfsm.hrawcb.hipvar.hifether.h
udp.htcpip.hresolv.hmbuf.hinpcb.h
Data Structures
Several important data structures are used by the socket library routines. The data structures are
provided in the header files in the $SYSTEM.ZTCPIP subvolume. Table 11 lists the data structures,
indicating the page where its documented and the C header file in which each structure is declared
as well as the type of routine that uses that structure.
Table 11 Summary Data Structures and C Header Files
Type of Routine That Uses StructureHeader FileStructure
Supportnetdb.haddrinfo (page 64)
Socket I/Oifarp.harpreq (page 65)
Supportnetdb.hhostent (page 66)
Socket I/Oif.hif_nameindex (page 67)*
Socket I/Oif.hifreq (page 68)
Socketin.hin_addr (page 69)
Socketin.hin6_addr (page 70)*
Socket I/Oin.hipv6_mreq (page 71)*
Supportnetdb.hnetent (page 71)
Supportnetdb.hopen_info_message (page 72)
Supportnetdb.hprotoent (page 73)
Socket I/Oroute.hrtentry (page 74)
Socket (send_nw)netdb.hsend_nw_str (page 75)
Socketin.hsendto_recvfrom_buf (page 76)
Supportnetdb.hservent (page 76)
Socketnetdb.hsockaddr (page 77)
Socketin.hsockaddr_in (page 78)
Socketin.hsockaddr_in6 (page 78)*
Socketin.hsockaddr_storage (page 79)*
* Applies to NonStop TCP/IPv6 only
See Chapter 4 (page 81), for more information about the different types of socket library calls;
the socket function calls are listed in Table 12 (page 82). The socket I/O control operations are
socket_ioctl and socket_ioctl_nw. The socket I/O control operations and the structures
they use are listed in Table 16 (page 199).
Data Structures 63