This same code works on other platforms. Also this is part of a bigger
application. If i write the exact same code as a small test
application it works fine. I cannot find the difference.

int db2esqlConnect(const char *databaseEnv,
                  const char *username,
                  const char *password,
                  ERRCB *ep)
{
 EXEC SQL BEGIN DECLARE SECTION;
    char dbsql[10];
    char usersql[20];
    char passwdsql[20];
    short numTables;
 EXEC SQL END DECLARE SECTION;
 int rc;
 long prev_code = 0;

 strcpy(dbsql, databaseEnv);
 memset(&sqlca, 0, sizeof(struct sqlca));
 /* connect to database */

if (username && *username && password && *password) {
  strcpy(usersql, username);
  strcpy(passwdsql, password);
  EXEC SQL CONNECT TO  :dbsql USER :usersql USING :passwdsql;
}
else {
  EXEC SQL CONNECT TO  :dbsql;
}

 if (SQLCODE == 0) {
    strncpy(Sversion_, sqlca.sqlerrp, 8);
    Sversion_[8] = '\0';
    strcpy(dbname, databaseEnv);
 }
 else
 {
   return FALSE;
 }
}