PQtrace doesn't work - Mailing list pgsql-general

From W. van den Akker
Subject PQtrace doesn't work
Date
Msg-id 401917DF.5030001@wilsoft.nl
Whole thread Raw
In response to A strange Vacuum error ...  (Dave Smith <dave.smith@candata.com>)
Responses Re: PQtrace doesn't work  (Tom Lane <tgl@sss.pgh.pa.us>)
PQtrace doesn't work  ("W. van den Akker" <listsrv@wilsoft.nl>)
List pgsql-general
Hello,

I have a little test program (see at the end of the message). The program
crashes when PQTrace is called (instruction xxxx referenced memory at
"0x00000010", the
memory could not be written" (obvious ... )
I use the library libpqdll.lib and postgresql v7.3.4. When I comment the
line the program runs fine.

Any ideas?

gr,

Willem.


#include <stdio.h>
#include <stdlib.h>
#include <libpq-fe.h>
#include <winsock.h>

void main ()
{
    int  nFields;
    int     i, j;

    PGconn    *conn;
    PGresult *res;

    char *pghost = "linux";
    char *dbName = "some_db";

    FILE *debug;

    WSADATA  wsadata;
    WSAStartup(0x0101, &wsadata);

    conn = PQsetdbLogin (pghost, NULL, NULL, NULL, dbName, "user","");

    if (PQstatus(conn) == CONNECTION_BAD)
    {
        printf ("Connection to database %s is failed\n", dbName);
        printf ("%s", PQerrorMessage (conn));
        PQfinish (conn);
        exit (1);
    }

    debug = fopen ("trace.out", "w");
  --->>  PQtrace (conn, debug);

    res = PQexec (conn, "BEGIN");
    if (!res || PQresultStatus (res) != PGRES_COMMAND_OK)
    {
        printf ("BEGIN command failed\n");
        PQclear (res);
        PQfinish (conn);
        exit (1);
    }

    PQclear (res);

    res = PQexec (conn, "DECLARE mycursor CURSOR FOR select sum(id) from
relaties");
    if (!res || PQresultStatus (res) != PGRES_COMMAND_OK)
    {
        printf ("DECLARE CURSOR command failed\n");
        PQclear (res);
        PQfinish (conn);
        exit (1);
    }

    PQclear (res);
    res = PQexec (conn, "FETCH ALL in mycursor");
    if (!res || PQresultStatus (res) != PGRES_TUPLES_OK)
    {
        printf ("FETCH ALL command didn't return tuples properly\n");
        PQclear (res);
        PQfinish (conn);
        exit (1);
    }

    nFields = PQnfields (res);
    for (i = 0; i < nFields; i++)
        printf ("%-15s", PQfname (res, i));

    printf ("\n\n");

    for (i = 0; i < PQntuples (res); i++)
    {
        for (j = 0; j < nFields; j++)
            printf ("%-15s", PQgetvalue (res, i, j));
        printf ("\n");
    }

    PQclear (res);

    res = PQexec (conn, "CLOSE mycursor");
    PQclear (res);

    res = PQexec (conn, "COMMIT");
    PQclear (res);

    PQfinish (conn);

    fclose (debug);

    WSACleanup();
}



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