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GETHOSTENT(3N)                                                  GETHOSTENT(3N)



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

SYNOPSIS
       #include <&lt;netdb.h>&gt;

       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()

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:

       h_name      Official name of the host.

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

       h_addrtype  The  type  of  address  being  returned;  currently  always
                   AF_INET.

       h_length    The length, in bytes, of the address.

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

       Gethostent reads the next line of the file, opening the file if  neces-
       sary.

       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  gethos-
       tent (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

SEE ALSO
       hosts(5)

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.



4th Berkeley Distribution       9 February 1983                 GETHOSTENT(3N)