fstat in PHP

fstat — Gets information about a file using an open file pointer
Syntax:

array fstat ( resource $handle )
Gathers the statistics of the file opened by the file pointer handle. This function is similar to the stat() function except that it operates on an open file pointer instead of a filename.

Parameters:

handle
A file system pointer resource that is typically created using fopen().

Return values: Returns an array with the statistics of the file; the format of the array is described in detail on the stat() manual page.



Example #1 fstat() example

<?php

// open a file
$fp = fopen("/etc/passwd", "r");

// gather statistics
$fstat = fstat($fp);

// close the file
fclose($fp);

// print only the associative part
print_r(array_slice($fstat, 13));

?>
The above example will output something similar to:

Array
(
    [dev] => 771
    [ino] => 488704
    [mode] => 33188
    [nlink] => 1
    [uid] => 0
    [gid] => 0
    [rdev] => 0
    [size] => 1114
    [atime] => 1061067181
    [mtime] => 1056136526
    [ctime] => 1056136526
    [blksize] => 4096
    [blocks] => 8
)


Note: This function will not work on remote files as the file to be examined must be accessible via the server's filesystem.

array slice in PHP

array slice() function is used to extract selected part from input array.

Syntax:

array_slice(array,start,length,preserve)

Parameters Description:

array : Required. Specifies an array

begin : Required. Numeric value. Specifies where the function will begin the slice. 0 = the first element. In the value that this value is situated to a negative number, the function will start slicing that last from the final component. -2 methods start at the second last element of the array.

length : Optional. Numeric value. Indicates the length of the returned array.
If this value is not set, the function will return all elements, starting from the position set by the start-parameter.
preserve : Optional.
      Possible values:

• true -  Preserve keys
• false - Default - Reset keys

Example:

<?php
$daysarr1 = array( 0=>"Sunday",1=>"Monday",2=>"Tuesday",3=>"Wednesday" ); 

print_r(array_slice($daysarr1,1,2));
$daysarr2 = array( 0=>"Sunday",1=>"Monday",2=>"Tuesday",3=>"Wednesday" );
echo "using negative start parameter";
print_r(array_slice($daysarr2,-2,1)); 
$daysarr3 = array( 0=>"Sunday",1=>"Monday",2=>"Tuesday",3=>"Wednesday" );
echo "using preserve parameter set to true"; 
print_r(array_slice($daysarr3,1,2,true));
print_r($daysarr3); 
$daysarr4 = array( "a"=>"Sunday","b"=>"Monday","c"=>"Tuesday","d"=>"Wednesday" );
echo "using string keys";
print_r(array_slice($daysarr4,1,2));
?>

O/P:

Array ( 
          [0] => Monday 
          [1] => Tuesday 
         )
using negative start parameter
Array (
         [0] => Tuesday
        )
using preserve parameter set to true
Array ( 
          [1] => Monday
          [2] => Tuesday
        )
using string keys
Array (
          [b] => Monday 
          [c] => Tuesday
        )