#include <ssdef.h>		/* system services		*/
#include <errno.h>		/* error numbers and codes	*/
#include <descrip.h>		/* vms descriptors		*/
#include <lnmdef.h>		/* logical names defs		*/
#include <psldef.h>		/* processor status fields	*/

#define MAXHOSTNAMELEN	64	/* maximum host name length	*/
#define TABLE_NAME	"LNM$SYSTEM_TABLE"
#define LOGICAL_NAME	"ARPANET_HOST_NAME"	/* Wollongong	*/

static char	hostname[MAXHOSTNAMELEN]; /* local buffer	*/

#ifndef min(a,b)
#define	min(a,b)	((a-b > 0) ? b : a)
#endif /* min */

int	gethostname(name, namelen)
char	*name;
int namelen;
{
	short	hostnamel;
	int	rc;
	unsigned long		attr;
	struct dsc$descriptor	tabnam;
	struct dsc$descriptor	lognam;
	unsigned char		acmode;	
	struct	{
		unsigned short	len;
		unsigned short	code;
		char		*bufaddr;
		unsigned short	*retlen;
		int	eoi;
	}	itemlist = 
		{ sizeof(hostname), LNM$_STRING , hostname, &hostnamel, 0 };
	attr = LNM$M_CASE_BLIND;
	tabnam.dsc$w_length = strlen(TABLE_NAME);
	tabnam.dsc$a_pointer = TABLE_NAME;
	tabnam.dsc$b_class = DSC$K_CLASS_S;
	tabnam.dsc$b_dtype = DSC$K_DTYPE_T;
        lognam.dsc$w_length = strlen(LOGICAL_NAME);
        lognam.dsc$a_pointer = LOGICAL_NAME;
        lognam.dsc$b_class = DSC$K_CLASS_S;
	lognam.dsc$b_dtype = DSC$K_DTYPE_T;
	acmode = PSL$C_USER;

	rc = sys$trnlnm(&attr, &tabnam, &lognam, &acmode, &itemlist);
	
	if (!(rc & 0x01))       {
		vaxc$errno = rc;
		errno = EVMSERR;
		return(-1);
	}
	else	{
		strncpy(name,hostname,min(namelen,hostnamel));
		name[min(namelen,hostnamel)] ='\0';
		return (0);
	}
}

#if defined(DEBUG) && defined(MAIN)
#include <stdio.h>		/* standard input/output defs.	*/
main()	{
	char name[MAXHOSTNAMELEN];

	if (gethostname(name,sizeof(name)))	{
		fprintf(stdout,"Unable to get hostname\n");
		perror("hostname");
	}
	else	{
		fprintf(stdout,"Hostname: <%s>\n",hostname);
	}
}
#endif /* DEBUG && MAIN */