fprintf
    (PHP 5)
fprintf -- Write a formatted string to a stream
Description
int 
fprintf ( resource handle, string format [, mixed args [, mixed ...]] )
     Write a string produced according to format
     to the stream resource specified by handle.
     format is described in the documentation for
     sprintf().
    
     Returns the length of the outputted string.
    
     See also: printf(),
     sprintf(),
     sscanf(), fscanf(), 
     vsprintf(), and
     number_format().
    
Examples
     
Example 1. fprintf(): zero-padded integers 
<?php if (!($fp = fopen('date.txt', 'w')))     return;
  fprintf($fp, "%04d-%02d-%02d", $year, $month, $day); // will write the formatted ISO date to date.txt ?>
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     Example 2. fprintf(): formatting currency 
<?php if (!($fp = fopen('currency.txt', 'w')))     return;
  $money1 = 68.75; $money2 = 54.35; $money = $money1 + $money2; // echo $money will output "123.1"; $len = fprintf($fp, '%01.2f', $money); // will write "123.10" to currency.txt
  echo "wrote $len bytes to currency.txt"; // use the return value of fprintf to determine how many bytes we wrote ?>
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