PHP | SplFileObject ftruncate() Function

The SplFileObject::ftruncate() function is an inbuilt function of Standard PHP Library (SPL) in PHP which is used to truncates the file size in bytes.

Syntax:

bool SplFileObject::ftruncate( $length )

Parameters: This function accept single parameter $length which specified the length of truncate of the file.

Return values: This function returns True on success or False on failure.

Below Programs illustrate the SplFileObject ftruncate() function in PHP:

Program 1:

<?php

// Create a file named "gfg.txt" which
// containing data "GeeksforGeeks"
$gfg = new SplFileObject("gfg.txt", "w+");
$gfg->fwrite("GeeksforGeeks");

// Truncate file
$gfg->ftruncate(8);

// Rewind and reading data from file
$gfg->rewind();

// Print result after truncate
echo $gfg->fgets();
?>

Output:

Geeksfor

Program 2:

<?php

// Create an Array
$GFG = array(
    "dummy.txt",
    "gfg.txt",
    "frame.txt"
    );

// Creating Spl Object
foreach ($GFG as &$arr) {
    $file = new SplFileObject($arr);

    // Truncate file
    $file->ftruncate(8);

    // Rewind and reading data from file
    $file->rewind();

    // Print result after truncate
    echo $file->fgets();
}
?>

Output:

Geeksfor
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Reference: http://php.net/manual/en/splfileobject.ftruncate.php