gethostent(3N-xs)             (X/OPEN SOCKETS)            gethostent(3N-xs)

NAME
     gethostent, gethostbyaddr, gethostbyname, sethostent, endhostent -
     network host database functions

SYNOPSIS
     cc [flag ...] file ... -lxnet [library ...]

     #include <netdb.h>

     extern int herrno;

     void endhostent(void);

     struct hostent *gethostbyaddr(const void *addr, sizet len, int type);

     struct hostent *gethostbyname(const char *name);

     struct hostent *gethostent(void);

     void sethostent(int stayopen);

DESCRIPTION
     The gethostent, gethostbyaddr, and gethostbyname functions each return
     a pointer to a hostent structure, the members of which contain the
     fields of an entry in the network host database.

     The gethostent function reads the next entry of the database, opening
     a connection to the database if necessary.

     The gethostbyaddr function searches the database from the beginning
     and finds the first entry for which the address family specified by
     type matches the haddrtype member and the address pointed to by addr
     occurs in haddrlist, opening a connection to the database if neces-
     sary. The addr argument is a pointer to the binary-format (that is,
     not null-terminated) address in network byte order, whose length is
     specified by the len argument. The datatype of the address depends on
     the address family. For an address of type AFINET, this is an inaddr
     structure, defined in <netinet/in.h>.

     The gethostbyname function searches the database from the beginning
     and finds the first entry for which the host name specified by name
     matches the hname member, opening a connection to the database if
     necessary.

     The sethostent function opens a connection to the network host data-
     base, and sets the position of the next entry to the first entry. If
     the stayopen argument is non-zero, the connection to the host database
     will not be closed after each call to gethostent (either directly, or
     indirectly through one of the other gethost* functions).

     The endhostent function closes the connection to the database.




Page 1                       Reliant UNIX 5.44                Printed 11/98

gethostent(3N-xs)             (X/OPEN SOCKETS)            gethostent(3N-xs)

RETURN VALUE
     On successful completion, gethostbyaddr, gethostbyname and gethostent
     return a pointer to a hostent structure if the requested entry was
     found, and a null pointer if the end of the database was reached or
     the requested entry was not found. Otherwise, a null pointer is
     returned.

     On unsuccessful completion, gethostbyaddr and gethostbyname functions
     set herrno to indicate the error.

ERRORS
     No errors are defined for endhostent, gethostent, and sethostent.

     The gethostbyaddr and gethostbyname functions will fail in the follow-
     ing cases, setting herrno to the value shown in the list below. Any
     changes to errno are unspecified.

     HOSTNOTFOUND  No such host is known.

     TRYAGAIN       A temporary and possibly transient error occurred,
                     such as a failure of a server to respond.

     NORECOVERY     An unexpected server failure occurred which cannot be
                     recovered.

     NODATA         The server recognized the request and the name but no
                     address is available. Another type of request to the
                     name server for the domain might return an answer.

APPLICATION USAGE
     The gethostent, gethostbyaddr and gethostbyname functions may return
     pointers to static data, which may be overwritten by subsequent calls
     to any of these functions.

     These functions are generally used with the Internet address family.

SEE ALSO
     byteorder(3N-xs), getservent(3N-xs), inet(3N-xs), netdb(5).
















Page 2                       Reliant UNIX 5.44                Printed 11/98