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11 BenutzerBeiträge:
- Beiträge aktualisieren...
Anonymous
16.10.2009 10:54
to clarify:

in unix/linux:
hardlinks (by this function) cannot go across different filesystems.
softlinks can point anywhere.

in linux, hardlinking to directory is not permited.
albertpeschar at gmail dot com
28.05.2008 17:20
>> Be aware that the filesystem of the target and the link must be the same,
>> otherwise the link will fail! (Linking files over different filesystems doesn't work under Unix).

Using debian sid, 2.6.24-17-generic, that is definitely not true.
Tim McCormack
28.03.2008 2:04
As others have noted, the parameter order can seem a little awkward. Here's a mnemonic for remembering the order:

In UNIX, commands go like this:

> command input output

The link command is no different:

> ln infile outfile

...and PHP respects that convention.
Jasper Bekkers
6.03.2008 18:08
Due to the acquisition of Winternals by Microsoft, the previous link to junction.exe doesn't work anymore. The file has been moved to http://www.microsoft.com/technet/
sysinternals/FileAndDisk/Junction.mspx

(without the newline)
me at robhaswell dot co dot uk
10.01.2008 3:56
For those that find the order of the arguments unclear, here is a more verbose description:

<?php

$source
= "something.ext"; // This is the file that already exists
$dest = "newfile.ext"; // This the filename that you want to link it to

link($source, $dest);
?>
stephane AT baladeauboutdumonde DOT com
6.08.2007 20:45
Make link recursively :
<?php
function makeRecusLink($orig, $dest)
{
    if (
is_dir($orig)) {
        if (
substr($orig, -1) != '/') {
           
$orig .= '/';
        }

       
$handle = opendir($orig);

        while (
false !== ($file = readdir($handle))) {
            if (
$file != '.' && $file != '..') {
               
$path = $orig.$file;

                if (
is_file($path)) {
                    @
link($path, $dest.'/'.$file);
                } else if (
is_dir($path)) {
                    @
mkdir($dest.'/'.$file, 0755);                   
                   
makeRecusLink($path, $dest.'/'.$file);
                }
            }
        }
    }
   
   
closedir($handle);
}
?>
root at c-works dot net
5.01.2007 10:58
Be aware that the filesystem of the target and the link must be the same, otherwise the link will fail! (Linking files over different filesystems doesn't work under Unix).
Jasper Bekkers
2.08.2006 16:16
For a backup utility I needed link-like functionality on a windows system. As it isn't availible on windows, i tried to do it myself with the help of some tools. All you need is junction.exe from sysinternals in your %PATH%.

<?php
if(!function_exists('link')){ // Assume a windows system
   
function link($target, $link){
        if(
is_dir($target)){
           
// junctions link to directories in windows
           
exec("junction $link $target", $lines, $val);
            return
0 == $val;
        }elseif(
is_file($target)){
           
// Hardlinks link to files in windows
           
exec("fsutil hardlink create $link $target", $lines, $val);
            return
0 == $val;
        }
       
        return
false;
    }
}
?>

http://www.sysinternals.com/Utilities/Junction.html
Guilherme Garnier
25.04.2006 20:32
I noticed that, differently from Unix ln command, the second parameter can´t be a directory name, i.e., if you want to create a link with the same filename of the target file (obviously on different directories), you must specify the filename on the link parameter.

Example:
Unix ln command:
ln /dir1/file /dir2/   // ok, creates /dir2/file link

PHP link function:
link ("/dir1/file", "/dir2/");   // wrong, gives a "File exists" warning
link ("/dir1/file", "/dir2/file");   // ok, creates /dir2/file link
mmap at upt dot org
15.05.2004 13:28
I think kop is confused regarding the semantics of link's argument order.  The user's comment states that target should not already exist, suggesting that it is the target that is being created.   As with the UNIX hardlink, ln(1), the target is the existing file.  I think kop meant to say php's link() will return an error if the second parameter, the link being created, already exists.

Also, as with the UNIX system call link will fail if the link being created exists on a different filesystem.
kop at meme dot com
25.09.2003 11:20
Note that link() will not work if the target already exists, at least as of php 4.1.2.



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