Acabo de volver a probar el código y no me guarda las variables de sesión de página en página.
el código es:
index.php
<?php
session_start();
$id=$_GET["id"];
if (isset($id)==true){
echo "<DIV id= id style='visibility:visible;overflow:hidden;position :absolute;z-index:87;left:104px;top:65px;'>";
$nom=$_SESSION['nombre'];
echo "<font face='Verdana' size='2'>Bienvenido Sr. $nom </font>";
echo "</DIV>";
}else{
echo "<DIV id= id style='visibility:visible;overflow:hidden;position :absolute;z-index:87;left:104px;top:2px;'>";
echo "<font face='Verdana' size='2'>";
echo "<FORM NAME ='form1' METHOD ='post' ACTION = 'usuarios.php'>";
echo "<font face='Verdana' size='2'>Usuario : </font><INPUT TYPE = 'TEXT' VALUE ='' STYLE='font-family: Verdana; font-size: 12px;' NAME= 'username' ><br><br>";
echo "<font face='Verdana' size='2'>Contraseña : </font><INPUT TYPE = 'password' VALUE ='' STYLE='font-family: Verdana; font-size: 12px;' NAME = 'pwd'><br>";
echo "<INPUT TYPE = 'Submit' Name = 'Submit1' STYLE='font-family: Verdana; font-size: 12px;' VALUE = 'Iniciar Sesion'>";
echo "</FORM>";
echo "</font>";
echo "</DIV>";
}
?>
usuarios.php
<?php
$username = $_POST['username'];
$pwd = $_POST['pwd'];
$conexion = mysql_connect("localhost", "web", "1234");
mysql_select_db("pueblo", $conexion);
$result = mysql_query("SELECT * FROM usuarios where usu='" . $username ."' and pwd='" . $pwd . "'");
while($row = mysql_fetch_array($result)){
session_register($row['id_usu']);
session_name ($row['id_usu']);
session_start();
$_SESSION['aut']= 1;
$_SESSION['nombre']= $row['apel1'];
header('Location: index.php?id=' . $row['id_usu']);
}
mysql_close($conexion);
?>
Y el Warning que me sale es:
Warning: session_start() [function.session-start]: Cannot send session cache limiter - headers already sent (output started at C:\x\xampplite\htdocs\pueblo\Web\index.php:19) in C:\x\xampplite\htdocs\pueblo\Web\index.php on line 20