gethostent(3N)                                     gethostent(3N)



     NAME
          gethostent, gethostbyaddr, gethostbyname, sethostent,
          endhostent - get network host entry

     SYNOPSIS
          #include <netdb.h>

          struct hostent *gethostent()

          struct hostent *gethostbyname(name)
          char *name;

          struct hostent *gethostbyaddr(addr, len, type)
          char *addr; int len, type;

          sethostent(stayopen)
          int stayopen

          endhostent()

          cc ... -lnet

     DESCRIPTION
          gethostent, gethostbyname, and gethostbyaddr each return a
          pointer to an object with the following structure containing
          the broken-out fields of a line in the network host data
          base, /etc/hosts.

          struct    hostent {
             char  *h_name;       /*official name of host*/
             char  **h_aliases;   /*alias list*/
             int   h_addrtype;    /*address type*/
             int   h_length;      /*length of address*/
             char  *h_addr;       /*address*/
          };

          The members of this structure are:

          hname       Official name of the host.

          haliases    A zero terminated array of alternate names for
                       the host.

          haddrtype   The type of address being returned; currently
                       always AFINET.

          hlength     The length, in bytes, of the address.

          haddr       A pointer to the network address for the host.
                       Host addresses are returned in network byte
                       order.




     Page 1                                        (last mod. 1/14/87)

     gethostent(3N)                                     gethostent(3N)



          gethostent reads the next line of the file, opening the file
          if necessary.

          sethostent opens and rewinds the file.  If the stayopen flag
          is non-zero, the host data base will not be closed after
          each call to gethostent (either directly, or indirectly
          through one of the other ``gethost'' calls).

          endhostent closes the file.

          gethostbyname and gethostbyaddr sequentially search from the
          beginning of the file until a matching host name or host
          address is found, or until EOF is encountered.  Host
          addresses are supplied in network order.

     FILES
          /etc/hosts

     LINKING
          This library is accessed by specifying -lnet as the last
          argument to the compile line, e.g.:

            cc -o prog prog.c -lnet

     SEE ALSO
          hosts(4N)

     DIAGNOSTICS
          Null pointer (0) returned on EOF or error.

     BUGS
          All information is contained in a static area so it must be
          copied if it is to be saved.  Only the Internet address
          format is currently understood.





















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