is_file
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');
}
?>
is_link
(PHP 4, PHP 5)
is_link — Prüft, ob der Dateiname ein symbolischer Link ist
Beschreibung
bool is_link
( string
$filename
)Prüft, ob der angegebene Dateiname ein symbolischer Link ist.
Parameter-Liste
-
filename -
Pfad zur Datei.
Rückgabewerte
Gibt TRUE zurück, wenn der Dateiname existiert und es sich um
einen symbolischen Link handelt, sonst FALSE.
Beispiele
Beispiel #1 Erstelle und bestätige, dass eine Datei ein symbolischer Link ist
<?php
$link = 'uploads';
if (is_link($link)) {
echo readlink($link);
} else {
symlink('uploads.php', $link);
}
?>
Fehler/Exceptions
Im Fehlerfall wird eine E_WARNING ausgegeben.
Anmerkungen
Hinweis: Die Ergebnisse dieser Funktion werden gecached. Weitere Details erhalten Sie bei clearstatcache().
Tipp
Seit PHP 5.0.0 kann diese Funktion mit einigen URL-Wrappern benutzt werden. Schauen Sie in der Liste unter Unterstützte Protokolle and Wrappers nach, welcher Wrapper die Funktionalität von stat() unterstützt.
Siehe auch
- is_dir() - Prüft, ob der angegebene Dateiname ein Verzeichnis ist
- is_file() - Prüft, ob der Dateiname eine reguläre Datei ist
- readlink() - Liefert das Ziel eines symbolischen Links
add a note
User Contributed Notes
is_link
PaulE
02-Jun-2009 02:03
foobarfarter
18-Oct-2008 03:06
@radon8472 at hotmail dot com
The windows .lnk-things are real files, the explorer only treats them like links. Try to open one with Win+R->"notepad X:\Path\Visiblefilename.lnk You will see much 0-Bytes, but the linked path is displayed right on the screen. It should be possible to do the same by php.
radon8472 at hotmail dot com
31-Jul-2008 09:38
This function returns "false" for windows *.lnk files (tested under windows XP).
filetype also returns "file" an not "link" like expected.
I didn`t find a solution for this.
mbirth at webwriters dot de
20-May-2008 08:24
To find out whether a file is hardlinked to another filename, check the number of links of the stat() output. If it is >1 there is another filename for that file.
To find out whether two filenames are pointing to the same file, check the inode number of those 2 filenames. If it is equal, the 2 filenames are hardlinked together.
neverpanic->gmail[com]
30-Dec-2006 02:50
For me (Debian Sarge VPS) is_link returns true even for directories if you don't add a trailing slash to the filename.
<?php
if ($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)
brendy at gmail dot com
05-May-2006 07:22
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 ( $target == "" ? false : true );
}
?>
jr at cnb dot uam dot es
30-May-2005 11:31
Why don't you just try
is_dir("$pathname/.")
instead?
If $pathname is a directory, $pathname/. is itself and is a directory too.
If $pathname is a link to a directory, then $pathname/. is the actual directory pointed at and is a directory as well.
If $pathname is a link to a non-directory, then $pathname/. does not exist and returns FALSE, as it should.
A lot easier, more readable and intuitive.
andudi at gmx dot ch
02-Jun-2002 10:44
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
aris at riponce dot com
27-Mar-2001 02:27
If you test a symbolic (soft) link with is_file() it will return true. Either use filetype() which always returns the correct type OR make sure that you FIRST test with is_link() before you do with is_file() to get the correct type.