I have this code on a php mail form that I didn't use until recently.
//Open last-order.txt file for getting the order number
$readFile = fopen("./order.txt", "r") or die("Unable to open file!");
$orden= fread($readFile,filesize("./order.txt"));
fclose($readFile);
++$orden;
$writeFile= fopen("./order.txt", "w") or die("Unable to open file!");
fwrite($writeFile, $orden);
fclose($writeFile);
if (!preg_match("~^(?:f|ht)tps?://~i", $website)) $website = "http://" . $website;
$website = filter_var($website, FILTER_VALIDATE_URL);
$email = filter_var(trim($_POST["email"]), FILTER_SANITIZE_EMAIL);
$participantes = filter_var($_POST["participantes"], FILTER_SANITIZE_STRING, FILTER_FLAG_NO_ENCODE_QUOTES);
It references a TXT file called order.txt, which reads the file and increments the number by one each time it is read. Unfortunately, when the hosting provider gave me the cold shoulder, I lost this file and was unable to access the server or its backups.
This is the text I put in the TXT file:
Orden: 8000
I'm not really a proficient PHP coder, so I tried to recreate it or make it work, but to no avail.
This is an error:
[03-Jan-2023 13:29:22 America/Mexico_City] PHP Warning: Undefined variable $email_content in /home/guillerm/iefa.com.mx/rsvp/php/reserve.php on line 78 [03-Jan-2023 13:29:22 America/Mexico_City] PHP Warning: Cannot modify header information - headers already sent by (output started at /home/guillerm/iefa.com.mx/rsvp/php/reserve.php:78) in /home/guillerm/iefa.com.mx/rsvp/php/reserve.php on line 149
Any help pointing me in the right direction would be greatly appreciated. Thank you for viewing this content.
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it's literally just supposed to be a number. replace
Orden: 8000with just8000.BTW, this code is thread-unsafe , the numbers may conflict/duplicate if you run multiple instances of the code concurrently; if you need to be thread-safe, you can do this
$readFile = fopen("./order.txt", "c+b") or die("Unable to open file!"); flock($readFile, LOCK_EX); $orden = (int)stream_get_contents($readFile); ++$orden; rewind($readFile); fwrite($readFile, (string) $orden); flock($readFile, LOCK_UN); fclose($readFile);