file in PHP

file — Reads entire file into an array
Syntax:

array file ( string $filename [, int $flags = 0 [, resource $context ]] )
Reads an entire file into an array.

Note:
You can use file_get_contents() to return the contents of a file as a string.
Parameters:

filename
Path to the file.

Tip
A URL can be used as a filename with this function if the fopen wrappers have been enabled. See fopen() for more details on how to specify the filename. See the Supported Protocols and Wrappers for links to information about what abilities the various wrappers have, notes on their usage, and information on any predefined variables they may provide.
flags
The optional parameter flags can be one, or more, of the following constants:

FILE_USE_INCLUDE_PATH
Search for the file in the include_path.
FILE_IGNORE_NEW_LINES
Do not add newline at the end of each array element
FILE_SKIP_EMPTY_LINES
Skip empty lines
context
A context resource created with the stream_context_create() function.

Note: Context support was added with PHP 5.0.0. For a description of contexts, refer to Streams.
Return values: Returns the file in an array. Each element of the array corresponds to a line in the file, with the newline still attached. Upon failure, file() returns FALSE.

Note:
Each line in the resulting array will include the line ending, unless FILE_IGNORE_NEW_LINES is used, so you still need to use rtrim() if you do not want the line ending present.
Note: If PHP is not properly recognizing the line endings when reading files either on or created by a Macintosh computer, enabling the auto_detect_line_endings run-time configuration option may help resolve the problem.
Changelog ¶

Version Description
4.3.0 file() became binary safe


Example #1 file() example

<?php
// Get a file into an array.  In this example we'll go through HTTP to get
// the HTML source of a URL.
$lines = file('http://www.example.com/');

// Loop through our array, show HTML source as HTML source; and line numbers too.
foreach ($lines as $line_num => $line) {
    echo "Line #<b>{$line_num}</b> : " . htmlspecialchars($line) . "<br />\n";
}

// Another example, let's get a web page into a string.  See also file_get_contents().
$html = implode('', file('http://www.example.com/'));

// Using the optional flags parameter since PHP 5
$trimmed = file('somefile.txt', FILE_IGNORE_NEW_LINES | FILE_SKIP_EMPTY_LINES);
?>


Warning
When using SSL, Microsoft IIS will violate the protocol by closing the connection without sending a close_notify indicator. PHP will report this as "SSL: Fatal Protocol Error" when you reach the end of the data. To work around this, the value of error_reporting should be lowered to a level that does not include warnings. PHP 4.3.7 and higher can detect buggy IIS server software when you open the stream using the https:// wrapper and will suppress the warning. When using fsockopen() to create an ssl:// socket, the developer is responsible for detecting and suppressing this warning.