How to read only first three lines of file?

pablogosse

Hi all. I know the file() function reads a file into an array of lines, but is there a way to access only the first three lines of a file without having to read in the whole file?

Thanks,
P.

wizkid

Hi,

from the PHP manual:

file -- Reads entire file into an array

wizkid

intenz

Try...

$arrFile = file('foo.txt');
for($i = 0; $i < 3; $i++)
        echo $arrFile[$i] . "<br>\n";

mcgiddin

<?php

$file = "input.txt";
$fp = fopen($file, "r");
for($i=0; $i<3; $i++) {
  $buffer[$i] = fgets($fp);
}
fclose($fp);

?>

references:

http://www.php.net/manual/en/function.fopen.php
http://www.php.net/manual/en/function.fgets.php
http://www.php.net/manual/en/function.fclose.php

VS-Lap

How would you output the last line of a file? The contents of the file contains;

testing 123 | ! blah blah <test>
testing | great | headache !
ok pull hair from head | blah blah

It must also output all characters.

pablogosse

This will do what you're looking for.

$f = file("file.txt");
echo $f[count($f)-1];

Cheers,
Pablo

VS-Lap

Originally posted by pablogosse
This will do what you're looking for.

$f = file("file.txt");
echo $f[count($f)-1];

Cheers,
Pablo

Thanks! Could you review the below code. I'm trying to output the last 20 lines of a file. I know this is not the neat way, could you suggest a simple clean way.

<?
$f = file("../../../logs/c.channel");
print $f[count($f)-20];
print " ";
print $f[count($f)-10];
print " ";
print $f[count($f)-18];
print " ";
print $f[count($f)-17];
print " ";
print $f[count($f)-16];
print " ";
print $f[count($f)-15];
print " ";
print $f[count($f)-14];
print " ";
print $f[count($f)-13];
print " ";
print $f[count($f)-12];
print " ";
print $f[count($f)-11];
print " ";
print $f[count($f)-10];
print " ";
print $f[count($f)-9];
print " ";
print $f[count($f)-8];
print " ";
print $f[count($f)-7];
print " ";
print $f[count($f)-6];
print " ";
print $f[count($f)-5];
print " ";
print $f[count($f)-4];
print " ";
print $f[count($f)-3];
print " ";
print $f[count($f)-2];
print " ";
print $f[count($f)-1];
?>

xblue

probably cleaner to use a for loop as in the example above, but decrementing. something like

for($i=count($f)-1; $i>=count($f)-20; $i--) {
    print $f[$i]; 
}

cgraz

$f = file("../../../logs/c.channel"); 

for($i=20; $i>=1; $i--) {
   print $f[count($f)-$i] . "<br>";
}

Cgraz