/**********************************************************************
* FILENAME :       ListEnvironmentAttribute.c
*
* DESCRIPTION :
*       Example uses SQLGetEnvAttr() to obtain and display environment
*       attributes
*
* ODBC USAGE :
* 	SQLGetEnvAttr() - to obtain values for attributes:
*
* 	SQL_ATTR_CONNECTION_POOLING
*           - reports whether connection pooling is on or off and and
*             whether a pool is available per driver or per environment.
* 	      Values - SQL_CP_OFF, SQL_CP_ONE_PER_DRIVER or
*             SQL_CP_ONE_PER_HENV
*             SQL_ATTR_CP_MATCH
*           - reports how a connection is chosen from a pool.
*             Values - SQL_CP_STRICT_MATCH or SQL_CP_RELAXED_MATCH
*       SQL_ATTR_ODBC_VERSION
*           - reports whether application exhibits ODBC 2.x or ODBC 3.x
*             behaviour.
*             Values - SQL_OV_ODBC3_80, SQL_OV_ODBC3 or SQL_OV_ODBC2
*       SQL_ATTR_OUTPUT_NTS
*           - reports whether string returned by the driver are null
*             terminated
*             Values - SQL_TRUE or SQL_FALSE
*/
#include <stdio.h>
#include <stdlib.h>
#include <sql.h>
#include <sqlext.h>
#include <string.h>

#include "util.c"

main () {

    // Environment handle
    SQLHENV  	henv  = SQL_NULL_HENV;

    // For SQL_ATTR_CONNECTION_POOLING, SQL_ATTR_CP_MATCH
    SQLUINTEGER	uIntVal;

    // For SQL_ATTR_ODBC_VERSION, SQL_ATTR_OUTPUT_NTS
    SQLINTEGER  sIntVal;

    SQLRETURN retcode;				   // Return status


    // Allocate an environment handle
    retcode=SQLAllocHandle(SQL_HANDLE_ENV, SQL_NULL_HANDLE, &henv);
    CHECK_ERROR(retcode, "SQLAllocHandle(SQL_HANDLE_ENV)",
                henv, SQL_HANDLE_ENV);

    // Notify ODBC that this is an ODBC 3.0 app
    retcode = SQLSetEnvAttr(henv, SQL_ATTR_ODBC_VERSION,
                                        (SQLPOINTER) SQL_OV_ODBC3, 0);
    CHECK_ERROR(retcode, "SQLSetEnvAttr(SQL_HANDLE_ENV)",
                henv, SQL_HANDLE_ENV);

    printf ("\nEnvironment Attributes : \n");

    // Get Env attributes
    retcode = SQLGetEnvAttr (henv, SQL_ATTR_CONNECTION_POOLING,
                             (SQLPOINTER) &uIntVal,
                             (SQLINTEGER) sizeof(uIntVal), NULL);

    CHECK_ERROR(retcode, "SQLGetEnvAttr(SQL_ATTR_CONNECTION_POOLING)",
                henv, SQL_HANDLE_ENV);

    printf ("\nSQL_ATTR_CONNECTION_POOLING : ");
    if (uIntVal==SQL_CP_OFF) printf ("SQL_CP_OFF");
    if (uIntVal==SQL_CP_ONE_PER_DRIVER) printf ("SQL_CP_ONE_PER_DRIVER");
    if (uIntVal==SQL_CP_ONE_PER_HENV) printf ("SQL_CP_ONE_PER_HENV");

    // Caution: SQL_CP_DRIVER_AWARE may be undefined
    if (uIntVal==SQL_CP_DRIVER_AWARE)
    printf ("SQL_CP_DRIVER_AWARE");

    retcode = SQLGetEnvAttr (henv, SQL_ATTR_CP_MATCH,
                             (SQLPOINTER) &uIntVal,
                             (SQLINTEGER) sizeof(uIntVal), NULL);
    CHECK_ERROR(retcode, "SQLGetEnvAttr(SQL_ATTR_CP_MATCH)",
                henv, SQL_HANDLE_ENV);

    printf ("\nSQL_ATTR_CP_MATCH           : ");
    if (uIntVal==SQL_CP_STRICT_MATCH) printf ("SQL_CP_STRICT_MATCH");
    if (uIntVal==SQL_CP_RELAXED_MATCH) printf ("SQL_CP_RELAXED_MATCH");

    retcode = SQLGetEnvAttr (henv, SQL_ATTR_ODBC_VERSION,
                             (SQLPOINTER) &sIntVal,
                             (SQLINTEGER) sizeof(sIntVal), NULL);
    CHECK_ERROR(retcode, "SQLGetEnvAttr(SQL_ATTR_ODBC_VERSION)",
                henv, SQL_HANDLE_ENV);

    printf ("\nSQL_ATTR_ODBC_VERSION       : ");
    if (sIntVal==SQL_OV_ODBC3_80) printf ("SQL_OV_ODBC3_80");
    if (sIntVal==SQL_OV_ODBC3) printf ("SQL_OV_ODBC3");
    if (sIntVal==SQL_OV_ODBC2) printf ("SQL_OV_ODBC2");

    retcode = SQLGetEnvAttr (henv, SQL_ATTR_OUTPUT_NTS,
                             (SQLPOINTER) &sIntVal,
                             (SQLINTEGER) sizeof(sIntVal), NULL);
    CHECK_ERROR(retcode, "SQLGetEnvAttr(SQL_ATTR_OUTPUT_NTS)",
                henv, SQL_HANDLE_ENV);
    printf ("\nSQL_ATTR_OUTPUT_NTS         : ");
    if (sIntVal==SQL_TRUE) printf ("SQL_TRUE");
    if (sIntVal==SQL_FALSE) printf ("SQL_FALSE");

exit:

    printf ("\nComplete.\n");

    // Free Environment
    if (henv != SQL_NULL_HENV)
        SQLFreeHandle(SQL_HANDLE_ENV, henv);

    return 0;
}

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