php - find out the error in this code -

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• reference - error mean in php? 29 answers

<form action="" method="post">     username <input type="text" name="user"><br>      password <input type="password" name="pwd"><br>      <input type="submit" name="login" value="login">     <?php login(); ?> </form> 

this code give error that

fatal error: call undefined function login() in /var/www/trainees/bhupender/cms/admin.php on line 10.

this function.php files coding

function login() {

if(!isset($_post['username']))     return;  global $link; $query = "select * `b_user` username = '{$_post['username']}' , password = '{$_post['password']}'";  $result = mysqli_query($link, $query); $no_of_results = mysqli_num_rows($result); echo $no_of_results; if($no_of_results === 1){         $row = mysqli_fetch_array($result,mysqli_assoc);         $row['id'];         $_session['user_id'] = $row['id'];         header('location: manage.php');         exit; } else {     header('location: index.php');         exit; } 

}

why don't use

    <?php      function login() {     //function body }      if($_post) {        login();     }     ?> 

and html;

<form action="" method="post">     username <input type="text" name="user"><br>      password <input type="password" name="pwd"><br>      <input type="submit" name="login" value="login"> </form>