DataBlade API Programmer's Manual

DataBlade API Programmer's Manual
Chapter 5: Managing Sessions

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System Defaults

If a parameter described in an information structure is not set, the defaults are as follows.


Environment Variable	Type	Structure Member
`SERVERNUM`	integer	`MI_CONNECTION_INFO`.server_port
`INFORMIXSERVER`	string	`MI_CONNECTION_INFO`.server_name

Example: set_defaults

The following example shows one way to set defaults. Assume that the system parameter file sets the default database server to joe, the default database to test, and the default user to tester. Also assume that a particular application must connect to database server beth as user miadmin and open the template1 database every time it starts. To do this, the application sets its own default information structures, as the following code fragment illustrates. After setting the default connection with mi_set_default_connection_info() and the default database and user with mi_set_default_database_info(), the application makes the connection with mi_server_connect() and opens the database with mi_login(). (For a description of the all_callback() function, see "Callback Example".)

extern void MI_PROC_CALLBACK all_callback();
MI_CONNECTION							*conn;
MI_CONNECTION_INFO							cinfo;
MI_DATABASE_INFO							dinfo;

/* initialize LIBMI */
mi_register_callback(conn, MI_All_Events, 
	 all_callback, NULL, NULL);

/* assign values to the connection info */
cinfo.server_name = "beth";
cinfo.server_port = 0;

/* assign values to the database info */
dinfo.user_name = "miadmin";
dinfo.database_name = "template1";
dinfo.password = NULL;

/* set the application defaults */
if (mi_set_default_connection_info(&cinfo) ==
 MI_ERROR)
		printf("FAILED: mi_set_default_connection_info\n");
if (mi_set_default_database_info(&dinfo) ==
 MI_ERROR)
		printf("FAILED: mi_set_default_database_info\n");

/* get the application defaults */
mi_get_default_connection_info(&cinfo);

/* make sure we have the right database server */
if (strcmp("beth", cinfo.server_name) != 0)
	printf("FAILED: got server_name %s, should be beth\n",
		cinfo.server_name);
mi_get_default_database_info(&dinfo);

/* connect to database server 'beth' */
conn = mi_server_connect(&cinfo);
if (conn == NULL)
	printf("FAIL: CONNECT to beth\n");
else
{
		printf("OK: connected to %s\n",
		 cinfo.server_name);
		/* log in to `template1' as `miadmin' */
		if (mi_login(conn, &dinfo) != MI_ERROR)
    				printf("OK: connected to db %s\n",
    					dinfo.database_name);
		else
    				printf("FAILED: connect to db %s\n",
    					dinfo.database_name);
}

You can also use the following functions to get the system parameters from the application:

mi_sysname()
mi_get_parameter_info()

For complete descriptions of these functions, see Chapter 12, "DataBlade API Function Descriptions."

DataBlade API Programmer's ManualChapter 5: Managing Sessions Home Contents Index Master Index New Book

System Defaults

Example: set_defaults

DataBlade API Programmer's Manual
Chapter 5: Managing Sessions

Home Contents Index Master Index New Book