PHP 5.6.0beta1 released
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User Contributed Notes 8 notes

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2
mbirth at webwriters dot de
5 years ago
To find out whether a file is hardlinked to another filename, check the number of links of the stat() output. If it is >1 there is another filename for that file.

To find out whether two filenames are pointing to the same file, check the inode number of those 2 filenames. If it is equal, the 2 filenames are hardlinked together.
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1
PaulE
4 years ago
A workaround for Windows LNK files:

<?php

function _is_link($filename)
{
    if(
is_link($filename))
        return
true;

   
$ext = substr(strrchr($filename, '.'), 1);
    if(
strtolower($ext) == 'lnk')
    {
        return (
_readlink($filename) ? true : false);
    }

    return
false;
}

function
_readlink($file)
{
    if(
file_exists($file))
    {
        if(
is_link($file))
        {
            return
readlink($file);
        }

       
// Get file content
       
$handle = fopen($file, "rb");
       
$buffer = array();

        while(!
feof($handle))
        {
           
$buffer[] = fread($handle, 1);
        }

       
fclose($handle);

       
// Test magic value and GUID
       
if(count($buffer) < 20)
            return
false;
        if(
$buffer[0] != 'L')
            return
false;
        if((
ord($buffer[4]) != 0x01) ||
           (
ord($buffer[5]) != 0x14) ||
           (
ord($buffer[6]) != 0x02) ||
           (
ord($buffer[7]) != 0x00) ||
           (
ord($buffer[8]) != 0x00) ||
           (
ord($buffer[9]) != 0x00) ||
           (
ord($buffer[10]) != 0x00) ||
           (
ord($buffer[11]) != 0x00) ||
           (
ord($buffer[12]) != 0xC0) ||
           (
ord($buffer[13]) != 0x00) ||
           (
ord($buffer[14]) != 0x00) ||
           (
ord($buffer[15]) != 0x00) ||
           (
ord($buffer[16]) != 0x00) ||
           (
ord($buffer[17]) != 0x00) ||
           (
ord($buffer[18]) != 0x00) ||
           (
ord($buffer[19]) != 0x46))
        {
            return
false;
        }

       
$i = 20;
        if(
count($buffer) < ($i + 4))
            return
false;

       
$flags = ord($buffer[$i]);
       
$flags = $flags | (ord($buffer[++$i]) << 8);
       
$flags = $flags | (ord($buffer[++$i]) << 16);
       
$flags = $flags | (ord($buffer[++$i]) << 24);

       
$hasShellItemIdList = ($flags & 0x00000001) ? true : false;
       
$pointsToFileOrDir = ($flags & 0x00000002) ? true : false;

        if(!
$pointsToFileOrDir)
            return
false;

        if(
$hasShellItemIdList)
        {
           
$i = 76;
            if(
count($buffer) < ($i + 2))
                return
false;

           
$a = ord($buffer[$i]);
           
$a = $a | (ord($buffer[++$i]) << 8);
           
        }

       
$i = 78 + 4 + $a;
        if(
count($buffer) < ($i + 4))
            return
false;

       
$b = ord($buffer[$i]);
       
$b = $b | (ord($buffer[++$i]) << 8);
       
$b = $b | (ord($buffer[++$i]) << 16);
       
$b = $b | (ord($buffer[++$i]) << 24);

       
$i = 78 + $a + $b;
        if(
count($buffer) < ($i + 4))
            return
false;

       
$c = ord($buffer[$i]);
       
$c = $c | (ord($buffer[++$i]) << 8);
       
$c = $c | (ord($buffer[++$i]) << 16);
       
$c = $c | (ord($buffer[++$i]) << 24);

       
$i = 78 + $a + $b + $c;
        if(
count($buffer) < ($i +1))
            return
false;

       
$linkedTarget = "";
        for(;
$i < count($buffer); ++$i)
        {
            if(!
ord($buffer[$i]))
                break;

           
$linkedTarget .= $buffer[$i];
        }

        if(empty(
$linkedTarget))
            return
false;

       
        return
$linkedTarget;
    }

    return
false;
}

if(
_is_link('test.lnk'))
{
    echo
_readlink('test.lnk');
}
?>
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1
gggeek
6 months ago
On windows, take care that is_link returns false for Junctions.
Ways of telling apart a directory from a junction include doing both a stat() and and lstat() call and checking if there is any difference in the results
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0
foobarfarter
5 years ago
@radon8472 at hotmail dot com
The windows .lnk-things are real files, the explorer only treats them like links. Try to open one with Win+R->"notepad X:\Path\Visiblefilename.lnk You will see much 0-Bytes, but the linked path is displayed right on the screen. It should be possible to do the same by php.
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0
neverpanic->gmail[com]
7 years ago
For me (Debian Sarge VPS) is_link returns true even for directories if you don't add a trailing slash to the filename.
<?php
if ($dir{strlen($dir)-1} == '/') $dir = substr($dir, 0, -1);
is_link($dir);
?>
This works for me. It can't detect a symlink somewhere in a complete path, though (i.e. is_link(/www/somedir/file.php) will return false, just as is_link(/www/) would)
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0
brendy at gmail dot com
7 years ago
On Mac OSX, to see if a file is a FInder alias:

<?PHP
if( getFinderAlias( $someFile , $target ) ) {
 echo
$target;
}
else {
 echo
"File is not an alias";
}

function
getFinderAlias( $filename , &$target ) {
$getAliasTarget = <<< HEREDOC
    -- BEGIN APPLESCRIPT --
    set checkFileStr to "
{$filename}"
    set checkFile to checkFileStr as POSIX file
    try
        tell application "Finder"
            if original item of file checkFile exists then
                set targetFile to (original item of file checkFile) as alias
                set posTargetFile to POSIX path of targetFile as text
                get posTargetFile
            end if
        end tell
    end try
    -- END APPLESCRIPT --
HEREDOC;
$runText = "osascript << EOS\n{$getAliasTarget}\nEOS\n";
$target = trim( shell_exec( $runText ) );
return (
$target == "" ? false : true );
}
?>
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0
andudi at gmx dot ch
11 years ago
On my SuSE 7.2 is_link does not work on directories, but to find out, if a dir is a link, I use now this:

$linkdir = $path.$linkdirname;
if (realpath($linkdir) != realpath($path)."/".$linkdirname):
//$linkdir is a symbolic linked dir!
...

and this works fine :-)

Andreas Dick
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-1
radon8472 at hotmail dot com
5 years ago
This function returns "false" for windows *.lnk files (tested under windows XP).

filetype also returns "file" an not "link" like expected.

I didn`t find a solution for this.
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