Bruce Momjian wrote:
> Gerhard Häring wrote:
>
>>Why can't I send comments like
>>
>> -- a comment
>>
>>to the backend using libpq? Are these only handled in psql? Please allow to
>>send comments to the backend, as I really need them.
>
> The backend should handle them fine. Can you give us pgsql version and
> an example.
I experience it on 7.2.1 on Debian Woody here. Same on 7.3.1 AFAIK.
I attached a minimal libpq example in C (to rule out any interference
from my Python modules) that shows the problem.
-- Gerhard
/*
* testlibpq.c
*
* Test the C version of libpq, the PostgreSQL frontend
* library.
*/
#include <stdio.h>
#include <libpq-fe.h>
void
exit_nicely(PGconn *conn)
{
PQfinish(conn);
exit(1);
}
main()
{
char *pghost,
*pgport,
*pgoptions,
*pgtty;
char *dbName;
int nFields;
int i,
j;
/* FILE *debug; */
PGconn *conn;
PGresult *res;
/*
* begin, by setting the parameters for a backend connection if the
* parameters are null, then the system will try to use reasonable
* defaults by looking up environment variables or, failing that,
* using hardwired constants
*/
pghost = NULL; /* host name of the backend server */
pgport = NULL; /* port of the backend server */
pgoptions = NULL; /* special options to start up the backend
* server */
pgtty = NULL; /* debugging tty for the backend server */
dbName = "template1";
/* make a connection to the database */
conn = PQsetdb(pghost, pgport, pgoptions, pgtty, dbName);
/*
* check to see that the backend connection was successfully made
*/
if (PQstatus(conn) == CONNECTION_BAD)
{
fprintf(stderr, "Connection to database '%s' failed.\n", dbName);
fprintf(stderr, "%s", PQerrorMessage(conn));
exit_nicely(conn);
}
/* debug = fopen("/tmp/trace.out","w"); */
/* PQtrace(conn, debug); */
/* start a transaction block */
res = PQexec(conn, "-- foobar");
if (!res || PQresultStatus(res) != PGRES_COMMAND_OK)
{
fprintf(stderr, "couldn't process comment\n");
PQclear(res);
exit_nicely(conn);
}
/*
* should PQclear PGresult whenever it is no longer needed to avoid
* memory leaks
*/
PQclear(res);
/* close the connection to the database and cleanup */
PQfinish(conn);
/* fclose(debug); */
return 0;
}