PHP vfprintf() Function

The vfprintf() function is an inbuilt function in PHP that is used to write formatted information to a stream, such as a file or the output screen.

Syntax:

vfprintf(resource $stream, string $format, array $values): 

Parameters: This function accepts three parameters that are described below.

• $stream: This parameter tells you where you write the string. It could be a file or a standard output like a screen.
• $format: This is a template that shows how you want to arrange your data. It contains placeholders (like %d, %s, etc.) that represent where your actual data will go.
• $values: This array holds the actual data that will be inserted into the placeholders of the format string.

Return Values: The vfprintf() function returns the count of the character written to the screen. It will return an integer type

Program 1: The following program demonstrates the vfprintf() function.

<?php

$stream = fopen('./output.txt', 'w');
$values = [10, "Ram"];
$format = "Number: %d, Name: %s\n";
   
$result = vfprintf($stream, $format, $values);
   
fclose($stream);
   
if ($result >= 0) {
    echo "Successfully wrote $result characters to the file.";
} else {
    echo "An error occurred while writing to the file.";
}   

?>

Successfully wrote 22 characters to the file.

Program 2: The following program demonstrates the vfprintf() function.

<?php

$stream = fopen('php://stdout', 'w'); 
$values = ["Hello", "GPT-3.5", 2023];
$format = "Hello Geeks for Geeks .\n";
    
$result = vfprintf($stream, $format, $values);
    
if ($result >= 0) {
    echo "Successfully wrote $result characters to the screen.";
} else {
    echo "An error occurred while writing to the screen.";
}
    
fclose($stream);

?>

Hello Geeks for Geeks .
Successfully wrote 24 characters to the screen.

Reference: https://www.php.net/manual/en/function.vfprintf.php