hi all,
am trying to use C & C++ libraries with postgresql 7.2.
while compiling a sample programe(attached) there were thse errors
encounterd !..
[arindam@my src]$
[arindam@my src]$ gcc egTry.c
/tmp/ccTLiExh.o: In function `main':
/tmp/ccTLiExh.o(.text+0x12): undefined reference to `PQconnectdb'
/tmp/ccTLiExh.o(.text+0x2b): undefined reference to `PQstatus'
/tmp/ccTLiExh.o(.text+0x5c): undefined reference to `PQerrorMessage'
/tmp/ccTLiExh.o(.text+0xac): undefined reference to `PQexec'
/tmp/ccTLiExh.o(.text+0xc5): undefined reference to `PQresultStatus'
/tmp/ccTLiExh.o(.text+0xf3): undefined reference to `PQclear'
/tmp/ccTLiExh.o(.text+0x104): undefined reference to `PQfinish'
/tmp/ccTLiExh.o(.text+0x12e): undefined reference to `PQntuples'
/tmp/ccTLiExh.o(.text+0x159): undefined reference to `PQgetvalue'
/tmp/ccTLiExh.o(.text+0x186): undefined reference to `PQclear'
/tmp/ccTLiExh.o(.text+0x197): undefined reference to `PQfinish'
collect2: ld returned 1 exit status
[arindam@my src]$
lib & include dir are in /usr/lib/pgsql-7.2 & /usr/include/pgsql-7.2.
i have tried to compliethis programme with RH7.2(with postgres rpm & a
configured from tar file)..
i need help pls... i want to use C or C++
thanking u in advance
A.H
/*
* testlibpq.c Test the C version of Libpq, the Postgres frontend
* library.
* Sample Program 1
*/
#include <stdio.h>
#include <pgsql-7.2/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 = "masterdb";
/* 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, "BEGIN");
if (!res || PQresultStatus(res) != PGRES_COMMAND_OK)
{
fprintf(stderr, "BEGIN command failed\n");
PQclear(res);
exit_nicely(conn);
}
/*
* should PQclear PGresult whenever it is no longer needed to avoid
* memory leaks
*/
PQclear(res);
/*
* fetch instances from the pg_database, the system catalog of
* databases
*/
res = PQexec(conn, "DECLARE mycursor CURSOR FOR select * from pg_database");
if (!res || PQresultStatus(res) != PGRES_COMMAND_OK)
{
fprintf(stderr, "DECLARE CURSOR command failed\n");
PQclear(res);
exit_nicely(conn);
}
PQclear(res);
res = PQexec(conn, "FETCH ALL in mycursor");
if (!res || PQresultStatus(res) != PGRES_TUPLES_OK)
{
fprintf(stderr, "FETCH ALL command didn't return tuples properly\n");
PQclear(res);
exit_nicely(conn);
}
/* first, print out the attribute names */
nFields = PQnfields(res);
for (i = 0; i < nFields; i++)
printf("%-15s", PQfname(res, i));
printf("\n\n");
/* next, print out the instances */
for (i = 0; i < PQntuples(res); i++)
{
for (j = 0; j < nFields; j++)
printf("%-15s", PQgetvalue(res, i, j));
printf("\n");
}
PQclear(res);
/* close the cursor */
res = PQexec(conn, "CLOSE mycursor");
PQclear(res);
/* commit the transaction */
res = PQexec(conn, "COMMIT");
PQclear(res);
/* close the connection to the database and cleanup */
PQfinish(conn);
/* fclose(debug); */
return 0;
}
