if (PQstatus(conn) != CONNECTION_OK)
   {
      printf(stderr, "Connection to database '%s' failed.\n", PQdb(conn));
      printf(stderr, "%s", PQerrorMessage(conn));
   }

if(!res || PQresultStatus(res) != PGRES_TUPLES_OK)
        {
      printf(stderr,"%s",PQerrorMessage(conn));
        /*syslog(LOG_ERR, "CGMondb::SelectServerData - [%s] %s",
          PQresStatus(PQresultStatus(res)),
          PQresultErrorMessage(res));
        */
      PQclear(res);
      return (- 1 );
      }

dbname=# set client_encoding to KOI8;
SET
dbname=# sel;
ERROR:  п╬я┬п╦п╠п╨п╟ я│п╦пҐя┌п╟п╨я│п╦я│п╟ п╡ п╦п╩п╦ я─я▐пЄп╬п╪ "sel" at character  1 
LINE  1 : sel;
        ^