Download PostgreSQL 7.2 Programmer`s Guide

Chapter 1. libpq - C Library
* 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
char
int
int
*pghost,
*pgport,
*pgoptions,
*pgtty;
*dbName;
nFields;
i,
j;
/* FILE *debug; */
PGconn
PGresult
*conn;
*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); */
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