sql + C

hi.
who knows about C embebed (postgres + C)?
I have the program:

#include<string.h>
EXEC SQL BEGIN DECLARE SECTION;
VARCHAR base[50];
EXEC SQL END DECLARE SECTION;
EXEC SQL INCLUDE sqlca;
EXEC SQL DECLARE C77 CURSOR FOR select datname from pg_user,pg_database
where usename= :user and datdba=usesysid;
main ()
{
EXEC SQL CONNECT TO mybase;
if(sqlca.sqlcode < 0)
{
printf(" error");
exit(1);
}
// now I want to get results
EXEC SQL OPEN C77;
EXEC SQL FETCH IN C77 INTO :base; // here, it's the problem, I can't to
get the result on the base variable. I think that can be the variable
type. then how should be the data type for ":base" variable? ........
.......
.......
.....
...
.
.
.
.
pg_database has the attributes as follow:

mybase=> \d pg_database
Table "pg_database"
Attribute | Type | Modifier
-----------+---------+----------
datname | name | --->I can't to get the "datname"......why?
datdba | integer |
encoding | integer |
datpath | text |

I hope than you understand!

bye and thanks!