zoomtst5.c

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/*
 * $Id: zoomtst5.c,v 1.9 2002/02/28 13:21:16 adam Exp $
 *
 * Asynchronous multi-target client doing search, sort and present
 */

#include <stdio.h>
#include <string.h>

#include <yaz/nmem.h>
#include <yaz/xmalloc.h>
#include <yaz/zoom.h>

const char *my_callback (void *handle, const char *name)
{
    if (!strcmp (name, "async"))
	return "1";
    return 0;
}

int main(int argc, char **argv)
{
    int i;
    int no = argc-3;
    ZOOM_connection z[500]; /* allow at most 500 connections */
    ZOOM_resultset r[500];  /* and result sets .. */
    ZOOM_query q;
    ZOOM_options o;

    o = ZOOM_options_create ();
    if (argc < 4)
    {
	fprintf (stderr, "usage:\n%s target1 .. targetN query sort\n",
		 *argv);
	exit (2);
    }
    if (no > 500)
        no = 500;

    /* function my_callback called when reading options .. */
    ZOOM_options_set_callback (o, my_callback, 0);

    /* get 20 (at most) records from beginning */
    ZOOM_options_set (o, "count", "20");

    ZOOM_options_set (o, "implementationName", "sortapp");
    ZOOM_options_set (o, "preferredRecordSyntax", "usmarc");
    ZOOM_options_set (o, "elementSetName", "B");

    /* create query */
    q = ZOOM_query_create ();
    if (ZOOM_query_prefix (q, argv[argc-2]))
    {
	printf ("bad PQF: %s\n", argv[argc-2]);
	exit (1);
    }
    if (ZOOM_query_sortby (q, argv[argc-1]))
    {
	printf ("bad sort spec: %s\n", argv[argc-1]);
	exit (1);
    }
    /* connect - and search all */
    for (i = 0; i<no; i++)
    {
    	z[i] = ZOOM_connection_create (o);
    	ZOOM_connection_connect (z[i], argv[i+1], 0);
        r[i] = ZOOM_connection_search (z[i], q);
    }

    /* network I/O */
    while (ZOOM_event (no, z))
	;

    /* handle errors */
    for (i = 0; i<no; i++)
    {
	int error;
	const char *errmsg, *addinfo;
	if ((error = ZOOM_connection_error(z[i], &errmsg, &addinfo)))
	    fprintf (stderr, "%s error: %s (%d) %s\n",
		     ZOOM_connection_option_get(z[i], "host"),
		     errmsg, error, addinfo);
	else
	{
	    /* OK, no major errors. Look at the result count */
	    int pos;
	    printf ("%s: %d hits\n", ZOOM_connection_option_get(z[i], "host"),
		    ZOOM_resultset_size(r[i]));
	    /* go through first 20 records at target */
	    for (pos = 0; pos < 20; pos++)
	    {
		ZOOM_record rec;
		const char *db, *syntax, *str;
		int len;

		rec = ZOOM_resultset_record (r[i], pos);
		/* get database for record and record itself at pos */

		db = ZOOM_record_get (rec,  "database", 0);
		str = ZOOM_record_get (rec, "xml", &len);
		syntax = ZOOM_record_get (rec, "syntax", &len);
		/* if rec is non-null, we got a record for display */
		if (str)
		{
		    printf ("%d %s %s\n", pos+1, syntax, 
			    (db ? db : "unknown"));
		    if (rec)
			fwrite (str, 1, len, stdout);
		    printf ("\n");
		}
	    }
	}
    }

    /* destroy stuff and exit */
    ZOOM_query_destroy (q);
    for (i = 0; i<no; i++)
    {
        ZOOM_resultset_destroy (r[i]);
        ZOOM_connection_destroy (z[i]);
    }
    ZOOM_options_destroy(o);
    exit(0);
}