Thanks to everyone who replied. I'm sorry about being silent so long. I'd expected that the system would notify me when there were updates. Anyway I got on with my own solution, which was to write a C wrapper to gethostbyname that returned the address in a form my FORTRAN could access simply.
In the hope this may be of use to someone else or provoke more comments.
I wasn't aware of getaddrinfo. I'm using an old version of TCP/IP, with an older manual!
HP TCP/IP Services for OpenVMS Alpha Version V5.4 - ECO 7
on a AlphaStation 255/233 running OpenVMS V7.3-2
To run the example
$ @Test4
You'll want to specify a host name that exists
It seems I can't attach code examples, so I put in-line
TEST.FOR
PROGRAM TEST4
*+
*
* Program : TEST4
*
* Purpose : Test host name lookup
*
* Method :
*
* Called :
*
*
*-
* History :
* 03-Aug-2016 FJG Original version
*
** Include files **
*
INCLUDE 'sys$library:ucx$inetdef.for'
*
** Arguments **
* Given
* Modified
* Returned
*
** External routines **
*
INTEGER*4 get_host_address
EXTERNAL get_host_address
*
** Local parameters **
*
PARAMETER IBUFL=80
** Local variables **
*
CHARACTER*128 HOST_NAME
INTEGER*4 HOST_ADDRESS
*
PRINT *,'Entering program test4'
HOST_NAME = 'lpas3'! //CHAR(0)
HOST_ADDRESS = get_host_address(%REF(HOST_NAME), %VAL(5))
IF (HOST_ADDRESS .NE. 0) THEN
PRINT 300, 'Host address = ',HOST_ADDRESS,
& 'Host name =', HOST_NAME
300 FORMAT(A20, Z8, A20, A40)
ELSE
PRINT *, 'Host name not resolved'
ENDIF
PRINT *,'Exiting program test4'
=================================================================================
TEST4C.C
/*
* Test C function to lookup host name and return IP address
* to be linked with TEST4.FOR
*/
/*
* INCLUDE FILES:
*/
#include <in.h> /* define internet related constants, */
/* functions, and structures */
#include <inet.h> /* define network address info */
#include <netdb.h> /* define network database library info */
#include <socket.h> /* define BSD 4.x socket api */
#include <stdio.h> /* define standard i/o functions */
#include <stdlib.h> /* define standard library functions */
#include <string.h> /* define string handling functions */
#include <unixio.h> /* define unix i/o */
/*
* NAMED CONSTANTS:
*/
/*
* FORWARD REFERENCES:
*/
struct hostent * gethname(char *, int );
int get_host_address(char *, int);
int get_host_address(char * name, int length)
{
printf("Entering get_host_address\nName = %s\nlength = %d\n", name, length);
struct hostent* my_host_ent;
struct in_addr my_in_addr;
int host_address;
char terminated_host_name[length+1];
strncpy(terminated_host_name, name, length);
printf("copied string\n");
terminated_host_name[length] = 0; //terminate the string
printf("terminated_host_name = %.80s\n", terminated_host_name);
my_host_ent=gethostbyname(terminated_host_name);
printf("my_host_ent = %d\n", my_host_ent);
if (my_host_ent)
{
printf("h-name = %.80s\n", my_host_ent->h_name);
printf("h-length = %d\n", my_host_ent->h_length);
printf("h_addr = %X\n", my_host_ent->h_addr);
printf("h_addrtype = %X\n", my_host_ent->h_addrtype);
memcpy( &my_in_addr, my_host_ent->h_addr, sizeof(struct in_addr) );
printf("my_in_addr = %.80s\n",inet_ntoa(my_in_addr));
host_address = my_in_addr.S_un.S_addr;
printf("host_address = %X\n",host_address);
}
printf("Exiting get_host_address\n");
return(host_address);
}
===================================================================================
TEST4.COM
$ ! build, link, run TEST4 - program to test bind lookup
$ CC/PREFIX=ALL TEST4C.C
$ FOR TEST4
$ LINK/MAP/FULL TEST4,TEST4C
$ RUN TEST4
$!
$ EXIT
