What is the Purpose of php_eol in PHP?

in this quick PHP tutorial, We’ll discuss php_eol with examples. PHP_EOL is a predefined constant in PHP and represents an end-of-line character. It helps in dealing with text file I/O operations in PHP.

Linux and macOS represent the end-of-line marker by the newline character (\n), whereas Windows environments are represented by a combination of two characters a newline (\r\n).

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There are the following end-line characters used by the platform:

• Unix-based systems (e.g., Linux, macOS) typically use the newline character (\n) to represent the end of a line.
• Windows uses a combination of newline (\r\n) sequence.
• Classic Mac OS (pre-OS X) historically used only the carriage return (\r) character.

Writing to Files:

Let’s write a file that has two dummy lines and will use PHP_EOL, The PHP_EOL will add end-of-line marker based on the Operating system where the script is running.

$file = fopen('phpflow.txt', 'w');
fwrite($file, 'Line 1' . PHP_EOL);
fwrite($file, 'Line 2' . PHP_EOL);
fclose($file);

The above code will write two lines of text to a file named 'phpflow.txt'.

Concatenating Strings

We can also use PHP_EOL constant to concatenate ‘Hello’ and ‘World’ with the appropriate line break between them.

$message = 'Hello' . PHP_EOL . 'World';
echo $message;

PHP_EOL with Heredoc or Nowdoc Syntax:

We can also use php_eol constant with heredoc and newdoc.

$text = <<<EOT
This is a multiline string.
It spans multiple lines.
And ends here.
EOT;
echo $text . PHP_EOL;

Conclusion

We have discussed different scenarios to apply PHP_EOL with PHP application. You can add an end-line marker into your string into a text regardless of platform. You can create strings/file by using php_eol and it’ll apply end-of-line characters based on PHP platform environment. It helps to write cross-platform code that helps end-of-line endings.