<?php

$dbhost = 'localhost';
$dbusername = 'root';
$dbuserpassword = 'tiwss2011';
$default_dbname = 'mcell';

$MYSQL_ERRNO = '';
$MYSQL_ERROR = '';

function db_connect($dbname=''){

  global $dbhost, $dbusername, $dbuserpassword, $default_dbname;
  global $MYSQL_ERRNO, $MYSQL_ERROR;

  $link_id = mysql_connect($dbhost, $dbusername, $dbuserpassword);
  if(!$link_id){
    $MYSQL_ERRNO = 0;
    $MYSQL_ERROR = "connection failed to the host $dbhost.";
    return 0;
  }
  else if(empty($default_dbname) && !mysql_select_db($default_dbname)){
    $MYSQL_ERRNO = mysql_errno();
    $MYSQL_ERROR = mysql_error();
    return 0;
  }
  else if(empty($dbname) && !mysql_select_db($dbname)){
    $MYSQL_ERRNO = mysql_errno();
    $MYSQL_ERROR = mysql_error();
    return 0;
  }
  else {
    mysql_select_db($dbname);
    //echo $link_id;
    return $link_id;
  }
}

function sql_error(){
  global $MYSQL_ERRNO, $MYSQL_ERROR;

  if (empty($MYSQL_ERROR)){
    $MYSQL_ERRNO = mysql_errno();
    $MYSQL_ERROR = mysql_error();
  }
  return "$MYSQL_ERRNO: $MYSQL_ERROR";
}

?>