./configure && make && make install clean.

#include <stdio.h>
#include <stdlib.h>
main()
{
      printf ("Hello, world\n");
      exit (0);
}

gcc -o hello main.c

#include <stdio.h>
#include <stdlib.h>
#include <postgresql/libpq-fe.h>
main()
{
      const char conninfo[] = "dbname=database host=127.0.0.1 user=user password=password";
      char req[] = "DROP TABLE IF EXISTS sample"; 
      PGconn *conn;
      PGresult *res;
      conn = PQconnectdb (conninfo);
      res = PQexec (conn, req);
      printf ("Hello, PostgreSQL!\n");
      PQclear (res);
      PQfinish (conn);
      exit (0);
}

gcc -o hello main.c /usr/lib/libpq.so

xcompmgr -c &