Dbxckey()

PURPOSE

read current key

SYNOPSIS

#include "dbl.h"
 
	int	dbxckey(dbx, key, recno)
 
	<input parameters>
	char	*dbx;		/* Tagged index file descriptor			*/
 
	<output parameters>
	char	*key;		/* Address of a buffer where the current key is returned					*/
	long	*recno; 	/* Address of a buffer where the current record number associated with the key will be returned	*/

RETURN VALUE

The dbxckey() function returns 0 for success, or < 0 if an error occurs. See the section on return code values for a detailed list of return codes.

DESCRIPTION

The dbxckey() function reads the current key and its associated record number for the active tag from the specified tagged index file, .DBX.

EXAMPLE

The following example reads the current key and its associated record number from the VESSEL tag of the shipwreck table.

#include <stdio.h>
#include "dbl.h"		/* Recital/Library include file		*/
#include "dblproto.h"		/* Recital/Library prototype file	*/
 
	static	dBFIELD fields[6] = {
		"VESSEL",	'C',	18,	0,	0,
		"LAT",	'N',	4,	1,	0,
		"LONG",	'N',	4,	1,	0,
		"AMOUNT",	'N',	10,	0,	0,
		"DATE",	'D',	8,	0,	0,
		"FLAG",	'C',	9,	0,	0
	};
 
	static void errorproc(
		char	*func,
		char	*str,
		int	rc);
 
	main()
	{
	int	rc; 		/* Return Code for error handling	*/
	char	*dbf; 		/* File descriptor for table		*/
	char	*dbx; 		/* File descriptor for tagged index	*/
	char	record[58];	/* Array of char for records		*/
	char	status;		/* Deleted record flag			*/
	long	recno;		/* Table record variable		*/
	char	key[21];	/* Storage location for keys		*/
 
	rc = dbdcache(100);
	errorproc("dbdcache()","table cache specified.", rc);
	rc = dbicache(100);
	errorproc("dbicache()", "index cache specified.",rc);
	rc = dbfilemode(1,0);
	rc = dbopen("shipwreck.dbf", &dbf);
	errorproc("dbopen()","table opened in shared  mode.", rc);
	rc = dbxopen(dbf, "shipwreck.dbx", &dbx);
	errorproc("dbxopen()","tagged index opened.", rc);
 
	rc = dbxtkey(dbx, "Santa Rosa	  ", &recno, 0);
	errorproc("dbxtkey()", "record number found by key.", rc);
	printf("ttrecord number: t%dn", recno);
 
	rc = dbxgetrk(dbf, dbx, "Santa Rosa	  ", record, &status);
	errorproc("dbxgetrk()", "record retrieved by key.", rc);
	printf("tt%sn", record);
 
	rc = dbxckey(dbx, key, &recno);
	errorproc("dbxckey()", "current key read.", rc);
	printf("ttcurrent key: t%sn", key);
 
	rc = dbxclose(dbx);
	errorproc("dbxclose()", "tagged index closed.", rc);
	rc = dbclose(dbf);
	errorproc("dbclose()", "table closed.", rc);
 
	exit(0);
}
 
	static void errorproc(func, str, rc)
	char	*func;
	char	*str;
	int	rc;
{
	if ( rc != SUCCESS ) {
	printf("n  Error performing function %s -> %dn", func, rc);
	exit(1);
	}
	printf("Function: t%s, t%s - Okn", func, str);
	return;
}

SEE ALSO

dbxclose(), dbxgetrk(), dbxopen(), dbxtkey()