Plz help me how this php script working

[anambd2010]

when counting lines the following code used:

$tr = fgets($fo, $file_length);
$total_rows = $total_rows + 1;

here $tr variable created where used can't understand. plz anybody help me?

the full scrip is given below:


<?php

$file = "data1.txt";
//-----Opening the file data1.dat.
//-----Is displayed.
$fo =@fopen($file, "r") or die("Could not locate the specified
file! Please check If the file is valid.");

//-----Calculating the total size of the file - test.txt.
$file_length = filesize($file);
echo "The total size of the file is: $file_length", "\n";

//---Reading the entire file row-wise. Each time a line ends,
//newline character is met, the variable
//---$total_rows Is Incremented by 1.
$total_rows=0;
while(!(feof($fo)))
{
$tr = fgets($fo, $file_length);
$total_rows = $total_rows + 1;
}
echo
echo "Total number of lines in this file is: $total_rows ",
"\n";
//---Closing data1.dat for the next loop to execute successfully.
fclose($fo);
?>

[elephantecho]

Hello,

It is ($tr) not used in script anywhere, but it is needed. As fgets reads single line from memory at a time. It means it will stop reading when new-line / EOF is reached.

Here while blocks keeps incrementing $total_rows until EOF is reached, hence $total_rows returns total lines in the file.

But the code returns (total lines +1) every time .
To fix this there is a change in order of $tr line and $total_rows++ line, incrementing should come before
$tr=fgets($fo,$file_length).

Right Way:
while(!(feof($fo)))
{
$total_rows = $total_rows + 1;
$tr = fgets($fo, $file_length);

}