RE: SASL authentication

Hi, all:

The following is from MozLDAP document (http://www.mozilla.org/directory/csdk-docs/sasl.htm):
=========================================
Code Example 13-1 - Authenticating over SASL

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include "ldap.h"

int
main( int argc, char **argv )
{
    LDAP        *ld;
    LDAPMod     mod0;
    LDAPMod     mod1;
    LDAPMod     *mods[ 3 ];
    char        *vals0[ 2 ];
    char        *vals1[ 2 ];
    time_t      now;
    char        buf[ 128 ];
    struct berval   cred;
    struct berval   *servcred;
    int         version;
    /* get a handle to an LDAP connection */
    ......
    /* Set the LDAP protocol version supported by the client
       to 3. (By default, this is set to 2. SASL authentication
       is part of version 3 of the LDAP protocol.) */
    ......
    /* authenticate */
    cred.bv_val = "magic";
    cred.bv_len = sizeof( "magic" ) - 1;
    if ( ldap_sasl_bind_s( ld, "uid=bjensen,ou=people,dc=example,dc=com", \
      "babsmechanism", &cred, NULL, NULL, &servcred ) != LDAP_SUCCESS ) {
        ldap_perror( ld, "ldap_sasl_bind_s" );
        return( 1 );
    }
......
}
=========================================
My questions are:

1. The variable "cred" is set to "magic" in this example. What should it be in the real world? The user to be authenticated is already provided through the second parameter. So what is this "cred" for? Can I leave it as "magic", just like what is used in the example?

2. If I want to use GSSAPI to bind to the server, is the 3rd parameter to be passed as "GSSAPI"?

Thanks,
Xu Qiang