mail

(PHP 4, PHP 5, PHP 7, PHP 8)

mailSend mail

Description

mail(
    string $to,
    string $subject,
    string $message,
    array|string $additional_headers = [],
    string $additional_params = ""
): bool

Sends an email.

Parameters

to

Receiver, or receivers of the mail.

The formatting of this string must comply with » RFC 2822. Some examples are:

  • user@example.com
  • user@example.com, anotheruser@example.com
  • User
  • User , Another User

subject

Subject of the email to be sent.

Caution

Subject must satisfy » RFC 2047.

message

Message to be sent.

Each line should be separated with a CRLF (\r\n). Lines should not be larger than 70 characters.

Caution

(Windows only) When PHP is talking to a SMTP server directly, if a full stop is found on the start of a line, it is removed. To counter-act this, replace these occurrences with a double dot.

<?php
$text
= str_replace("\n.", "\n..", $text);
?>

additional_headers (optional)

String or array to be inserted at the end of the email header.

This is typically used to add extra headers (From, Cc, and Bcc). Multiple extra headers should be separated with a CRLF (\r\n). If outside data are used to compose this header, the data should be sanitized so that no unwanted headers could be injected.

If an array is passed, its keys are the header names and its values are the respective header values.

Note:

When sending mail, the mail must contain a From header. This can be set with the additional_headers parameter, or a default can be set in php.ini.

Failing to do this will result in an error message similar to Warning: mail(): "sendmail_from" not set in php.ini or custom "From:" header missing. The From header sets also Return-Path when sending directly via SMTP (Windows only).

Note:

If messages are not received, try using a LF (\n) only. Some Unix mail transfer agents (most notably » qmail) replace LF by CRLF automatically (which leads to doubling CR if CRLF is used). This should be a last resort, as it does not comply with » RFC 2822.

additional_params (optional)

The additional_params parameter can be used to pass additional flags as command line options to the program configured to be used when sending mail, as defined by the sendmail_path configuration setting. For example, this can be used to set the envelope sender address when using sendmail with the -f sendmail option.

This parameter is escaped by escapeshellcmd() internally to prevent command execution. escapeshellcmd() prevents command execution, but allows to add additional parameters. For security reasons, it is recommended for the user to sanitize this parameter to avoid adding unwanted parameters to the shell command.

Since escapeshellcmd() is applied automatically, some characters that are allowed as email addresses by internet RFCs cannot be used. mail() can not allow such characters, so in programs where the use of such characters is required, alternative means of sending emails (such as using a framework or a library) is recommended.

The user that the webserver runs as should be added as a trusted user to the sendmail configuration to prevent a 'X-Warning' header from being added to the message when the envelope sender (-f) is set using this method. For sendmail users, this file is /etc/mail/trusted-users.

Return Values

Returns true if the mail was successfully accepted for delivery, false otherwise.

It is important to note that just because the mail was accepted for delivery, it does NOT mean the mail will actually reach the intended destination.

Changelog

Version Description
7.2.0 The additional_headers parameter now also accepts an array.

Examples

Example #1 Sending mail.

Using mail() to send a simple email:

<?php
// The message
$message = "Line 1\r\nLine 2\r\nLine 3";

// In case any of our lines are larger than 70 characters, we should use wordwrap()
$message = wordwrap($message, 70, "\r\n");

// Send
mail('caffeinated@example.com', 'My Subject', $message);
?>

Example #2 Sending mail with extra headers.

The addition of basic headers, telling the MUA the From and Reply-To addresses:

<?php
$to
= 'nobody@example.com';
$subject = 'the subject';
$message = 'hello';
$headers = 'From: webmaster@example.com' . "\r\n" .
'Reply-To: webmaster@example.com' . "\r\n" .
'X-Mailer: PHP/' . phpversion();

mail($to, $subject, $message, $headers);
?>

Example #3 Sending mail with extra headers as array

This example sends the same mail as the example immediately above, but passes the additional headers as array (available as of PHP 7.2.0).

<?php
$to
= 'nobody@example.com';
$subject = 'the subject';
$message = 'hello';
$headers = array(
'From' => 'webmaster@example.com',
'Reply-To' => 'webmaster@example.com',
'X-Mailer' => 'PHP/' . phpversion()
);

mail($to, $subject, $message, $headers);
?>

Example #4 Sending mail with an additional command line parameter.

The additional_params parameter can be used to pass an additional parameter to the program configured to use when sending mail using the sendmail_path.

<?php
mail
('nobody@example.com', 'the subject', 'the message', null,
'-fwebmaster@example.com');
?>

Example #5 Sending HTML email

It is also possible to send HTML email with mail().

<?php
// Multiple recipients
$to = 'johny@example.com, sally@example.com'; // note the comma

// Subject
$subject = 'Birthday Reminders for August';

// Message
$message = '
<html>
<head>
<title>Birthday Reminders for August</title>
</head>
<body>
<p>Here are the birthdays upcoming in August!</p>
<table>
<tr>
<th>Person</th><th>Day</th><th>Month</th><th>Year</th>
</tr>
<tr>
<td>Johny</td><td>10th</td><td>August</td><td>1970</td>
</tr>
<tr>
<td>Sally</td><td>17th</td><td>August</td><td>1973</td>
</tr>
</table>
</body>
</html>
'
;

// To send HTML mail, the Content-type header must be set
$headers[] = 'MIME-Version: 1.0';
$headers[] = 'Content-type: text/html; charset=iso-8859-1';

// Additional headers
$headers[] = 'To: Mary <mary@example.com>, Kelly <kelly@example.com>';
$headers[] = 'From: Birthday Reminder <birthday@example.com>';
$headers[] = 'Cc: birthdayarchive@example.com';
$headers[] = 'Bcc: birthdaycheck@example.com';

// Mail it
mail($to, $subject, $message, implode("\r\n", $headers));
?>

Note:

If intending to send HTML or otherwise Complex mails, it is recommended to use the PEAR package » PEAR::Mail_Mime.

Notes

Note:

The SMTP implementation (Windows only) of mail() differs in many ways from the sendmail implementation. First, it doesn't use a local binary for composing messages but only operates on direct sockets which means a MTA is needed listening on a network socket (which can either on the localhost or a remote machine).

Second, the custom headers like From:, Cc:, Bcc: and Date: are not interpreted by the MTA in the first place, but are parsed by PHP.

As such, the to parameter should not be an address in the form of "Something <someone@example.com>". The mail command may not parse this properly while talking with the MTA.

Note:

It is worth noting that the mail() function is not suitable for larger volumes of email in a loop. This function opens and closes an SMTP socket for each email, which is not very efficient.

For the sending of large amounts of email, see the » PEAR::Mail, and » PEAR::Mail_Queue packages.

Note:

The following RFCs may be useful: » RFC 1896, » RFC 2045, » RFC 2046, » RFC 2047, » RFC 2048, » RFC 2049, and » RFC 2822.

See Also

add a note add a note

User Contributed Notes 39 notes

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21
Anonymous
4 years ago
If you notice wrong displayed characters in the email it's because you need to properly set the Content-Type and the Charset in the headers of the email:

<?php
$headers
= 'Content-Type: text/plain; charset=utf-8' . "\r\n";
?>

Mostly, UTF-8 is your best choice.

You can set custom headers with the fourth parameter of the mail() function.

To make the whole thing waterproof, add the following header too:

<?php
$headers
.= 'Content-Transfer-Encoding: base64' . "\r\n";
?>

Now you can use the combination of UTF-8 and Base64 to properly encode the subject line and the recipient name like this:

<?php
$subject
= '=?UTF-8?B?' . base64_encode('Test email with German Umlauts öäüß') . '?=';
$recipient = '=?UTF-8?B?' . base64_encode('Margret Müller') . '?= <recipient@domain.com>';
?>

And don't forget to Base64 encode the email message too:

<?php
$message
= base64_encode('This email contains German Umlauts öäüß.');
?>

All references are taken from:
https://dev.to/lutvit/how-to-make-the-php-mail-function-awesome-3cii
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10
Mark Simon
4 years ago
It is worth noting that you can set up a fake sendmail program using the sendmail_path directive in php.ini.

Despite the comment in that file, sendmail_path also works for Window. From https://www.php.net/manual/en/mail.configuration.php#ini.sendmail-path:

This directive works also under Windows. If set, smtp, smtp_port and sendmail_from are ignored and the specified command is executed.
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19
php at simoneast dot net
6 years ago
Often it's helpful to find the exact error message that is triggered by the mail() function. While the function doesn't provide an error directly, you can use error_get_last() when mail() returns false.

<?php
$success
= mail('example@example.com', 'My Subject', $message);
if (!
$success) {
   
$errorMessage = error_get_last()['message'];
}
?>

(Tested successfully on Windows which uses SMTP by default, but sendmail on Linux/OSX may not provide the same level of detail.)

Thanks to https://stackoverflow.com/a/20203870/195835
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16
Anonymous
7 years ago
Security advice: Although it is not documented, for the parameters $to and $subject the mail() function changes at least \r and \n to space. So these parameters are safe against injection of additional headers. But you might want to check $to for commas as these separate multiple addresses and you might not want to send to more than one recipient.

The crucial part is the $additional_headers parameter. This parameter can't be cleaned by the mail() function. So it is up to you to prevent unwanted \r or \n to be inserted into the values you put in there. Otherwise you just created a potential spam distributor.
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10
chris at ocproducts dot com
6 years ago
The 'sendmail' executable which PHP uses on Linux/Mac (not Windows) expects "\n" as a line separator.

This executable is a standard, and emulated by other MTAs.

"\n" is confirmed required for qmail and postfix, probably also for sendmail and exim but I have not tested.

If you pass through using "\r\n" as a separator it may appear to work, but your email will be subtly corrupted and some middleware may break. It only works because some systems will clean up your mistake.

If you are implementing DKIM be very careful, as DKIM checks will fail (at least on popular validation tools) if you screw this up. DKIM must be calculated using "\r\n" but then you must switch it all to "\n" when using the PHP mail function.

On Windows, however, you should use "\r\n" because PHP is using SMTP in this situation, and hence the normal rules of the SMTP protocol (not the normal rules of Unix piping) apply.
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7
charles dot fisher at arconic dot com
6 years ago
I migrated an application to a platform without a local transport agent (MTA). I did not want to configure an MTA, so I wrote this xxmail function to replace mail() with calls to a remote SMTP server. Hopefully it is of some use.

function xxmail($to, $subject, $body, $headers)
{
$smtp = stream_socket_client('tcp://smtp.yourmail.com:25', $eno, $estr, 30);

$B = 8192;
$c = "\r\n";
$s = 'myapp@someserver.com';

fwrite($smtp, 'helo ' . $_ENV['HOSTNAME'] . $c);
  $junk = fgets($smtp, $B);

// Envelope
fwrite($smtp, 'mail from: ' . $s . $c);
  $junk = fgets($smtp, $B);
fwrite($smtp, 'rcpt to: ' . $to . $c);
  $junk = fgets($smtp, $B);
fwrite($smtp, 'data' . $c);
  $junk = fgets($smtp, $B);

// Header
fwrite($smtp, 'To: ' . $to . $c);
if(strlen($subject)) fwrite($smtp, 'Subject: ' . $subject . $c);
if(strlen($headers)) fwrite($smtp, $headers); // Must be \r\n (delimited)
fwrite($smtp, $headers . $c);

// Body
if(strlen($body)) fwrite($smtp, $body . $c);
fwrite($smtp, $c . '.' . $c);
  $junk = fgets($smtp, $B);

// Close
fwrite($smtp, 'quit' . $c);
  $junk = fgets($smtp, $B);
fclose($smtp);
}
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8
ABOMB
12 years ago
I was having delivery issues from this function to Gmail, Yahoo, AOL, etc.  I used the notes here to figure that you need to be setting your Return-Path to a valid email to catch bounces.  There are two extra delivery gotchas on top of that:

1) The domain in the email used in the -f option in the php.ini sendmail parameter or in the mail() extra parameters field, needs to have a valid SPF record for the domain (in DNS as a "TXT" record type for sure and add an additional  "SPF" type record if possible).  Why? That's header field being used for spam checks.

2) You should also use a domain key or DKIM.  The trick here is that the domain key/DKIM is case sensitive!  I used Cpanel to create my domain key which automatically used all lowercase domain names in the key creation.  I found when  sending email and using a camel case "-f account@MyDomainHere.Com" option, my key was not accepted.  However it was accepted when I used "-f account@mydomainhere.com".

There are many other factors that can contribute to mail not getting to inboxes, including your own multiple failed testing attempts, so I suggest you consult each site's guidelines and don't ask me for help.  These are just the couple technical issues that helped my case.

I hope this saves someone some time and headaches...
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5
Ben Cooke
18 years ago
Note that there is a big difference between the behavior of this function on Windows systems vs. UNIX systems. On Windows it delivers directly to an SMTP server, while on a UNIX system it uses a local command to hand off to the system's own MTA.

The upshot of all this is that on a Windows system your  message and headers must use the standard line endings \r\n as prescribed by the email specs. On a UNIX system the MTA's "sendmail" interface assumes that recieved data will use UNIX line endings and will turn any \n to \r\n, so you must supply only \n to mail() on a UNIX system to avoid the MTA hypercorrecting to \r\r\n.

If you use plain old \n on a Windows system, some MTAs will get a little upset. qmail in particular will refuse outright to accept any message that has a lonely \n without an accompanying \r.
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5
pavel.lint at vk.com
11 years ago
Here's a small handy function I use to send email in UTF-8.

<?php
function mail_utf8($to, $from_user, $from_email,
                                            
$subject = '(No subject)', $message = '')
   {
     
$from_user = "=?UTF-8?B?".base64_encode($from_user)."?=";
     
$subject = "=?UTF-8?B?".base64_encode($subject)."?=";

     
$headers = "From: $from_user <$from_email>\r\n".
              
"MIME-Version: 1.0" . "\r\n" .
              
"Content-type: text/html; charset=UTF-8" . "\r\n";

     return
mail($to, $subject, $message, $headers);
   }
?>
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5
Porjo
13 years ago
Make sure you enclose \r\n in double quotes (not single quotes!) so that PHP can translate that into the correct linefeed code
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1
atesin () gmial ! com
2 years ago
HOW PHP MAIL() WORKS INTERNALLY, more or less, according some tests i did

imagine php is running with uid 33 when reaches a mail() function like this

---- /my/htdocs/mailer-script.php line 69 ----
$was_sent = mail(
  'Alice <alice@wonder.land>, white-rabbit@endless.cave',
  'Invitation',
  "Hi, you are cordially invited to drink a cup of tea at my house\ntomorrow at sunset",
  "Some-Header: foo\r\nOther-Header: bar", // can also be an associative array of 'Header' => 'Value'
  'param1 param2');
----

then look for ini options like this (all optional, on any operating system)

---- ini options ----
; path to mail sender command + arguments, if omitted will defaults to NULL
sendmail_path = '/bin/sendmail-esque arg1 arg2'
; the From header, can be also set in sendmail but make sure it SENDS ONE
sendmail_from = 'Mad Hatter <hatter@house.forest>'
; recommended to not being blind, look at file permissions
mail.log = '/var/log/php/mail.log'
; adds an originating script header to send php mail internals (security sensitive)
mail.add_x_header = on
; outgoing mail server address, if omitted will defaults to "localhost"
;SMTP = 'localhost'
; server tcp port, if omitted will defaults to port 25
;smtp_port = 25
----

then craft a message like this (please avoid duplicated headers)

---- mail message ----
From: Mad Hatter <hatter@house.forest>
To: Alice <alice@wonder.land>, white-rabbit@endless.cave
Subject: Invitation
Some-Header: foo
Other-Header: bar
X-PHP-Originating-Script: 33:mailer-script.php

Hi, you are cordially invited to drink a cup of tea at my house
tomorrow at sunset
----

then APPEND this log line

---- /var/log/php/mail.log ----
[<date> <time> <zone>] mail() on [/my/htdocs/mailer-script.php:69]: <all headers joined...>
----

THEN IF (sendmail_path is not empty, AND file is found, AND has +rx permissions):

- craft and run this shell command

---- shell ----
/bin/sendmail-esque arg1 arg2 param1 param2
----

- send the crafted message to its standard input
- wait the program to exit
- pass last exit code to mail() return

OR ELSE (i.e. sendmail bin not run) (not sure about these):

- try to internally open an smtp connection (with fsockopen()?)
- send the message directly and wait for connection to close
- pass last socket status to mail() return
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-1
eeeugeneee
6 years ago
Send mail with minimal requirements from email services.

<?php
    $encoding
= "utf-8";

   
// Preferences for Subject field
   
$subject_preferences = array(
       
"input-charset" => $encoding,
       
"output-charset" => $encoding,
       
"line-length" => 76,
       
"line-break-chars" => "\r\n"
   
);

   
// Mail header
   
$header = "Content-type: text/html; charset=".$encoding." \r\n";
   
$header .= "From: ".$from_name." <".$from_mail."> \r\n";
   
$header .= "MIME-Version: 1.0 \r\n";
   
$header .= "Content-Transfer-Encoding: 8bit \r\n";
   
$header .= "Date: ".date("r (T)")." \r\n";
   
$header .= iconv_mime_encode("Subject", $mail_subject, $subject_preferences);

   
// Send mail
   
mail($mail_to, $mail_subject, $mail_message, $header);
?>
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-1
Max AT
12 years ago
To define a mail sensitivity you have to put this line in the headers:

<?php
        $headers
= "MIME-Version: 1.0\n" ;
       
$headers .= "Content-Type: text/html; charset=\"iso-8859-1\"\n";

       
$headers .= "Sensitivity: Personal\n";

$status   = mail($to, $subject, $message,$headers);
?>

Possible Options:
Sensitivity: Normal, Personal, Private and Company-Confidential

These will be recognised and handled in Outlook, Thunderbird and others.
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-1
pangz dot lab at gmail dot com
3 years ago
* Sending email with attachment

function sendMail(
    string $fileAttachment,
    string $mailMessage = MAIL_CONF["mailMessage"],
    string $subject     = MAIL_CONF["subject"],
    string $toAddress   = MAIL_CONF["toAddress"],
    string $fromMail    = MAIL_CONF["fromMail"]
): bool {
   
    $fileAttachment = trim($fileAttachment);
    $from           = $fromMail;
    $pathInfo       = pathinfo($fileAttachment);
    $attchmentName  = "attachment_".date("YmdHms").(
    (isset($pathInfo['extension']))? ".".$pathInfo['extension'] : ""
    );
   
    $attachment    = chunk_split(base64_encode(file_get_contents($fileAttachment)));
    $boundary      = "PHP-mixed-".md5(time());
    $boundWithPre  = "\n--".$boundary;
   
    $headers   = "From: $from";
    $headers  .= "\nReply-To: $from";
    $headers  .= "\nContent-Type: multipart/mixed; boundary=\"".$boundary."\"";
   
    $message   = $boundWithPre;
    $message  .= "\n Content-Type: text/plain; charset=UTF-8\n";
    $message  .= "\n $mailMessage";
   
    $message .= $boundWithPre;
    $message .= "\nContent-Type: application/octet-stream; name=\"".$attchmentName."\"";
    $message .= "\nContent-Transfer-Encoding: base64\n";
    $message .= "\nContent-Disposition: attachment\n";
    $message .= $attachment;
    $message .= $boundWithPre."--";
   
    return mail($toAddress, $subject, $message, $headers);
}

* Sending email in html

function sendHtmlMail(
    string $mailMessage = MAIL_CONF["mailMessage"],
    string $subject     = MAIL_CONF["subject"],
    array $toAddress    = MAIL_CONF["toAddress"],
    string $fromMail    = MAIL_CONF["fromMail"]
): bool {
   
    $to        = implode(",", $toAddress);
    $headers[] = 'MIME-Version: 1.0';
    $headers[] = 'Content-type: text/html; charset=iso-8859-1';   
    $headers[] = 'To: '.$to;
    $headers[] = 'From: '.$fromMail;   

    return mail($to, $subject, $mailMessage, implode("\r\n", $headers));
}
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-2
rexlorenzo at gmail dot com
11 years ago
Be careful to not put extra spaces for the $headers variable.

For example, this didn't work on our servers:

$headers = "From: $from \r\n Bcc: $bcc \r\n";

But this did:

$headers = "From: $from\r\nBcc: $bcc\r\n";

Notice the removal of the spaces around the first \r\n.
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-2
jim at jimbrooking dot net
8 years ago
I recently changed hosting companies and spent a day trying to see why an email script that had been working for years failed on the new server.

The answer was that the old hosting company's email server accepted multiple "CC:" lines in the additional headers string, and the new did not. Thus on the new server

...
$add_hdr .= "CC: " . $email1 . PHP_EOL;
$add_hdr .= "CC: " . $email2 . PHP_EOL;
...

did not work, but

...
$add_hdr .= "CC: " . $email1 . ", " . $email2 . PHP_EOL;
...

did work.

In both cases, PHP's mail() function returned no error, but until I placed both emails, comma-separated, in the same line I was getting the following error:

550 Messages should have one or no Cc headers, not 2.

Hope this helps someone.
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-2
chris at ocproducts dot com
6 years ago
Correction to my earlier note:

'"\n" is confirmed required for qmail and postfix, probably also for sendmail and exim but I have not tested.'

It only affects qmail.
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-4
debis at woh dot rr dot com
12 years ago
This is for Windows Server 2003, IIS 6.0 with SMTP virtual server.

The problem I had was not including init_set for the SMTP server, I thought the SMTP definition in the IIS SMTP virtual server configuration would work.  When I sent mail manually this was not an issue. 

Also, $mail_sent = @mail( $to, $subject, $message, $headers ); wouldn't work but $mail_sent = mail($to, $subject, $message, $headers); did.
Lack of date_default_timezone_set() only caused a warning because php guessed what it should be.

This worked:
<?php
$to     
= 'nobody@example.com';
$subject = 'the subject';
$message = 'hello';
$headers = 'From: webmaster@example.com' . "\r\n" .
   
'Reply-To: webmaster@example.com' . "\r\n" .
   
'X-Mailer: PHP/' . phpversion();
ini_set ( "SMTP", "smtp-server.example.com" );
date_default_timezone_set('America/New_York');

mail($to, $subject, $message, $headers);
?>

And just so you can troubleshoot, this worked when sending mail from the command line/manually. CLI worked even though the php code without the init_set function wouldn't work.

You will notice that the "rcpt to" and "to" fields appear redundant, but if both are not used, the delivered mail's "to" field will be blank/empty.

-------------------------------
telnet www.example.com 25
helo
mail from: webmaster@example.com
rcpt to: someone@example.com
data
to: someone@example.com
subject: test again to make sure

this is my message
.
quit
-----------------------------------
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-8
jimmytrojan009 at gmail dot com
8 years ago
I have tried many online tutorials to get mail() function working in windows, until i stumbled upon this website
http://php.codeindepth.com/php-sending-mail/

It really boils down to changing few directives in php.ini and sendmail.ini

Changes required in sendmail.ini

smtp_server=smtp.gmail.com
smtp_port=587
error_logfile=error.log
debug_logfile=debug.log
auth_username=your-gmail-id@gmail.com
auth_password=your-gmail-password
force_sender=your-gmail-id@gmail.com

Changes required in php.ini

SMTP=smtp.gmail.com
smtp_port=587
sendmail_from = your-gmail-id@gmail.com
sendmail_path = "\"C:\xampp\sendmail\sendmail.exe\" -t"
;sendmail_path = "C:\xampp\mailtodisk\mailtodisk.exe"
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-5
richard at richard-sumilang dot com
15 years ago
If you are using the sendmail app from an exim package or something you don't really need to change the normal parameters PHP gives it (-t -i) as other posts described.

I just added "-f myemail@example.com" and it worked.

One thing that got me stuck for a few hours was trying to figure out why the return-path was set as the user (user running php) and not what I was setting it with the -f option then I later found at that in order to forcefully set the return-path the user account running the command must be in exim's trusted users configuration! It helps to add trusted_groups as well then everything works fine :)
- Richard Sumilang
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-5
bburch at bouncingpixel dot com
11 years ago
When using the PHP mail() function with IIS 6 on Windows Server 2003, check your "Relay" settings on the SMTP Virtual Server in IIS.  If you grant access to 127.0.0.1 and set then set your php.ini SMTP to the same IP address (along with setting the same port 25), you should have success in sending mail. 

I'm using PHP 5.3 and have had success with this configuration and did not have to define the "sendmail_from" setting in our php.ini file.
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Edward
14 years ago
Currently my hosting service is on Godaddy. When attempting to use the mail function without the fifth parameter containing "-f", my message headers would not work.

Whenever your message headers do not work, simply try using the fifth parameter:

<?php
mail
($to, $subject, $message, $headers, "-femail.address@example.com");
?>
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msheldon at desertraven dot com
18 years ago
Just a comment on some of the examples, and as a note for those who may be unaware. The SMTP RFC 822 is VERY explicit in stating that \r\n is the ONLY acceptable line break format in the headers, though is a little vague about the message body. While many MTAs will deal with just \n, I've run accross plenty of them that will exhibit "interesting" behaviours when this happens. Those MTAs that are strict in compliance will definitely break when header lines are terminated with only \n. They will also most likely break if the body of the message contains more than 1000 consecutive characters without a \r\n.*

Note that RFC 821 is a little more clear in defining:
"line
      A a sequence of ASCII characters ending with a <CRLF>."

RFC 821 makes no distinction between header lines and message body lines, since both are actually transmitted during the DATA phase.

Bottom line, best practice is to be sure to convert any bare \n characters in the message to \r\n.

* "The maximum total length of a text line including the <CRLF> is 1000 characters" (RFC 821)
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f dot touchard at laposte dot net
21 years ago
***Encoding plain text as quoted-printable in MIME email***

If you don't want to install IMAP and use imap_8bit() to encode plain text or html message as quoted-printable
(friendly french special characters encoding :-) in MIME email, try this function.
I haven't fully tested it ( like with microtime with long mails). I send html message as 7-bit, so I didn't try yet with html.
If you have good html practise, you don't really need to encode html as quote-printable as it only uses 7-bit chars.
F.Touchard

<?php
function qp_encoding($Message) {
   
   
/* Build (most polpular) Extended ASCII Char/Hex MAP (characters >127 & <255) */
   
for ($i=0; $i<127; $i++) {
       
$CharList[$i] = "/".chr($i+128)."/";
       
$HexList[$i] = "=".strtoupper(bin2hex(chr($i+128)));
    }

   
/* Encode equal sign & 8-bit characters as equal signs followed by their hexadecimal values */
   
$Message = str_replace("=", "=3D", $Message);
   
$Message = preg_replace($CharList, $HexList, $Message);

   
/* Lines longer than 76 characters (size limit for quoted-printable Content-Transfer-Encoding)
        will be cut after character 75 and an equals sign is appended to these lines. */
   
$MessageLines = split("\n", $Message);
   
$Message_qp = "";
    while(list(,
$Line) = each($MessageLines)) {
        if (
strlen($Line) > 75) {
           
$Pointer = 0;       
            while (
$Pointer <= strlen($Line)) {
               
$Offset = 0;
                if (
preg_match("/^=(3D|([8-9A-F]{1}[0-9A-F]{1}))$/", substr($Line, ($Pointer+73), 3))) $Offset=-2;
                if (
preg_match("/^=(3D|([8-9A-F]{1}[0-9A-F]{1}))$/", substr($Line, ($Pointer+74), 3))) $Offset=-1;
               
$Message_qp.= substr($Line, $Pointer, (75+$Offset))."=\n";
                if ((
strlen($Line) - ($Pointer+75)) <= 75) {               
                   
$Message_qp.= substr($Line, ($Pointer+75+$Offset))."\n";
                    break
1;
                }
               
$Pointer+= 75+$Offset;
            }
        } else {
           
$Message_qp.= $Line."\n";
        }
    }       
    return
$Message_qp;
}
?>
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molotster on google mail com
15 years ago
Note, that single line should not contain more than 78 character, but is not allowed to contain more than 998 characters.

The possible consequences are:
Over 78 - clients are allowed to display the message in a "harder to read" way.
Over 998 - clients and servers are allowed to drop the message or cause any buffer-limit error.

See:
http://www.faqs.org/rfcs/rfc2822 part 2.1.1.
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ittasks at gmail dot com
10 years ago
When dealing with mail headers "\n" and "\r\n" *sometimes* makes a big difference.

Once our CentOs servers got re-installed, all headers like:

  $headers = "MIME-Version: 1.0\r\n";
  $headers.= "Content-type: text/html; charset=iso-8859-1\r\n";
...

became part of message body instead of headers

I was able to fixed this by replacing "\r\n" with just "\n"
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Erich at gasboysnospam dot net
15 years ago
if your mail is failing (returns false) be aware that many servers are configured to kill mail going out with a bcc or cc header.

The ideal workaround is to use the smtp functions which servers allow because of its better audit trail. Alternatively call the mail function several times.

I've just spent about four hours trying to work out what I was doing wrong!!
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Alex Jaspersen
16 years ago
For qmail users, I have written a function that talks directly to qmail-queue, rather than going through the sendmail wrapper used by mail(). Thus it allows more direct control over the message (for example, you can adapt the function to display "undisclosed recipients" in to the To: header). It also performs careful validation of the e-mail addresses passed to it, making it more difficult for spammers to exploit your scripts.

Please note that this function differs from the mail() function in that the from address must be passed as a _separate_ argument. It is automatically put into the message headers and _does not_ need to be included in $additional_headers.

$to can either be an array or a single address contained in a string.
$message should not contain any carriage return characters - only linefeeds.

No validation is performed on $additional_headers. This is mostly unnecessary because qmail will ignore any additional To: headers injected by a malicious user. However if you have some strange mail setup it might be a problem.

The function returns false if the message fails validation or is rejected by qmail-queue, and returns true on success.

<?php
function qmail_queue($to, $from, $subject, $message, $additional_headers = "")
{
   
// qmail-queue location and hostname used for Message-Id
   
$cmd = "/var/qmail/bin/qmail-queue";
   
$hostname = trim(file_get_contents("/var/qmail/control/me"));
   
   
// convert $to into an array
   
if(is_scalar($to))
       
$to = array($to);
   
   
// BEGIN VALIDATION
    // e-mail address validation
   
$e = "/^[-+\\.0-9=a-z_]+@([-0-9a-z]+\\.)+([0-9a-z]){2,4}$/i";
   
// from address
   
if(!preg_match($e, $from)) return false;
   
// to address(es)
   
foreach($to as $rcpt)
    {
        if(!
preg_match($e, $rcpt)) return false;
    }
   
   
// subject validation (only printable 7-bit ascii characters allowed)
    // needs to be adapted to allow for foreign languages with 8-bit characters
   
if(!preg_match("/^[\\040-\\176]+$/", $subject)) return false;
   
   
// END VALIDATION
   
    // open qmail-queue process
   
$dspec = array
    (
        array(
"pipe", "r"), // message descriptor
       
array("pipe", "r") // envelope descriptor
   
);
   
$pipes = array();
   
$proc = proc_open($cmd, $dspec, $pipes);
    if(!
is_resource($proc)) return false;
   
   
// write additional headers
   
if(!empty($additional_headers))
    {
       
fwrite($pipes[0], $additional_headers . "\n");
    }
   
   
// write to/from/subject/date/message-ID headers
   
fwrite($pipes[0], "To: " . $to[0]); // first recipient
   
for($i = 1; $i < sizeof($to); $i++) // additional recipients
   
{
       
fwrite($pipes[0], ", " . $to[$i]);
    }
   
fwrite($pipes[0], "\nSubject: " . $subject . "\n");
   
fwrite($pipes[0], "From: " . $from . "\n");
   
fwrite($pipes[0], "Message-Id: <" . md5(uniqid(microtime())) . "@" . $hostname . ">\n");
   
fwrite($pipes[0], "Date: " . date("r") . "\n\n");
   
fwrite($pipes[0], $message);
   
fwrite($pipes[0], "\n");
   
fclose($pipes[0]);
   
   
// write from address and recipients
   
fwrite($pipes[1], "F" . $from . "\0");
    foreach(
$to as $rcpt)
    {
       
fwrite($pipes[1], "T" . $rcpt . "\0");
    }
   
fwrite($pipes[1], "\0");
   
fclose($pipes[1]);
   
   
// return true on success.
   
return proc_close($proc) == 0;
}
?>
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Systemx
14 years ago
Bare LFs in SMTP

Use This

<?php
// Fix any bare linefeeds in the message to make it RFC821 Compliant.
$message = preg_replace("#(?<!\r)\n#si", "\r\n", $message);
   
// Make sure there are no bare linefeeds in the headers
$headers = preg_replace('#(?<!\r)\n#si', "\r\n", $headers);
?>
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Paul
20 years ago
My mime multipart/alternative messages were going ok, until I switched to qmail with php .. after years of painfull searching, I came across this on the Life With Qmail 'Gotchas' section:

G.11. Carriage Return/Linefeed (CRLF) line breaks don't work

qmail-inject and other local injection mechanisms like sendmail don't work right when messages are injected with DOS-style carriage return/linefeed (CRLF) line breaks. Unlike Sendmail, qmail requires locally-injected messages to use Unix newlines (LF only). This is a common problem with PHP scripts.

So now, I can go back to sending emails with text AND html components :)
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martin dot farrow at versacloud dot com
11 years ago
I've noticed that on some versions of PHP occasionally mail() returns the empty string for success, rather than true or false. The empty string evaluates to false.

if you use constructs like

if ( mail( ... ) ){
  # do something here on success
}

this wont work consistently.

so you need code like

$ret=mail(....)

if ( $ret == '' || $ret ){
  # do something here
}

to get consistent results.
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John dot php at yaph dot org dot uk
3 years ago
I found I needed to use the additional parameter -f$envelope_sender to send subscribe messages to my email list manager (Enemies of Carlotta, YMMV). Simply setting From: email@address.tld in additional headers wasn't sufficient.

So to subscribe to mylist@example.com via a PHP script I call
mail("mylist-subscribe@example.com", $emailSubject, $body, '', "-f$email_to_subscribe");
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php dot net at schrecktech dot com
19 years ago
When sending MIME email make sure you follow the documentation with the "70" characters per line...you may end up with missing characters...and that is really hard to track down...
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marcrbarker at NOSPAMgmail dot com
3 years ago
DKIM signature can break by trying to add <HTML tag> text effects where plain text is expected:

.
.
.
$headers[] = 'MIME-Version: 1.0';
$headers[] = 'Content-Type: text/html; utf-8';
$headers[] = 'Content-Transfer-Encoding: quoted-printable';

// *** This will break DKIM ***
$message = '<span style="color:green;font-size:24px;">ThisIsColored</span>'
// *** This had broke DKIM ***

mail($email, $subject, $message, implode("\r\n", $headers));
.
.
.
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jerold at pangzlab dot com
4 years ago
Sending mail with attachments

function sendMail(
    $mailTo,
    $message,
    $subject    = "Your Subject",
    $fromMail   = "your@emialaddress.com",
    $fromName   = "from sender",
    $replyTo    = "no-reply",
    $filePath   = "path"
)
{
    $LE  = "\r\n";
    $uid = md5(uniqid(time()));
    $withAttachment = ($filePath !== NULL && file_exists($filePath));

    if($withAttachment){
        $fileName   = basename($filePath);
        $fileSize   = filesize($filePath);
        $handle     = fopen($filePath, "r");
        $content    = fread($handle, $fileSize);
        fclose($handle);
        $content = chunk_split(base64_encode($content));
    }

    $header = "From: ".$fromName." <".$fromMail.">$LE";
    $header .= "Reply-To: ".$replyTo."$LE";
    $header .= "MIME-Version: 1.0$LE";
    $header .= "Content-Type: multipart/mixed; boundary=\"".$uid."\"$LE$LE";
    $header .= "This is a multi-part message in MIME format.$LE";
    $header .= "--".$uid."$LE";
    $header .= "Content-type:text/html; charset=UTF-8$LE";
    $header .= "Content-Transfer-Encoding: 7bit$LE$LE";
    $header .= $message."$LE$LE";

    if($withAttachment){
        $header .= "--".$uid."$LE";
        $header .= "Content-Type: application/octet-stream; name=\"".$fileName."\"$LE";
        $header .= "Content-Transfer-Encoding: base64$LE";
        $header .= "Content-Disposition: attachment; filename=\"".$fileName."\"$LE$LE";
        $header .= $content."$LE$LE";
        $header .= "--".$uid."--";
    }
    return mail($mailTo, $subject, "", $header);
}
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umangberi at gmail dot com
13 years ago
Outlook 2007 seemed to be a little finicky with me to have carriage returns in the headers. So any \r\n resulted in messages that had default apache messages sent over to me.

As soon as I removed \r from all of the headers, the script started working fine. Hope that helped.
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yarik dot bohatsky at gmail dot com
11 years ago
If you want to send UTF-8 HTML letter you need to mention charset twice:

1) In message header:
<?php
$headers
.= 'Content-type: text/html; charset=utf-8' . "\r\n";
?>

2) In HTML header:
<?php
$message
= '
<html>
<head>
   <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
   <title>Fillon soutient à fond le retour d\'un Grand Prix de France</title>
</head>
<body>
   <p>Le Premier ministre François Fillon, passionné d\'automobile et pilote à ses heures, a apporté un soutien appuyé au retour d\'un Grand Prix de France au calendrier 2013 de la Formule 1, en faisant un passage-éclair vendredi sur le circuit Paul Ricard dans le Var.</p>
</body>
</html>
'
;

In this case Outlook will also "understand" that message is encoded using UTF-8.
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shuitest at gmail dot com
13 years ago
If you use mutt, do as below,

/usr/bin/mutt -s '$subject' -f /dev/null -e 'set copy=no' -e 'set from = "{$GLOBALS[cfg][email_from]}"' -a '$attach_file_full_path' '{$GLOBALS[cfg][email_to]}' </dev/null 2>&1;
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shenyqwilliam
11 years ago
If you're sending a large attachment, you may encounter overflow problem.
AFAIK, two common limits could be responsible.

1. Postfix message size limit.
Edit /etc/postfix/main.cf . Change the value of "message_size_limit".

2. Apache memory size limit for scripts.
Edit /etc/php.ini . Change the value of "memory_limit".

//Then reload (or restart) Postfix and Apache.
//Empirically, sending 200MB attachment requires 500MB memory.

Be careful! Raising memory limits may cause unexpected consequences, and is hence deprecated.
Recommended alternatives include:
* Pack and split attachment into several emails.
* Only include a link to the file. The receiver can download it later.
* Use IMAP/POP3 server (e.g. Dovecot).
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