Here's a fairly safe way to get the username from uid even if the posix extension isn't installed.
<?php
function GetUsernameFromUid($uid)
{
if (function_exists('posix_getpwuid'))
{
$a = posix_getpwuid($uid);
return $a['name'];
}
# This works on BSD but not with GNU
elseif (strstr(php_uname('s'), 'BSD'))
{
exec('id -u ' . (int) $uid, $o, $r);
if ($r == 0)
return trim($o['0']);
else
return $uid;
}
elseif (is_readable('/etc/passwd'))
{
exec(sprintf('grep :%s: /etc/passwd | cut -d: -f1', (int) $uid), $o, $r);
if ($r == 0)
return trim($o['0']);
else
return $uid;
}
else
return $uid;
}
?>
posix_getpwuid
(PHP 4, PHP 5)
posix_getpwuid — Restituisce le informazioni di un utente dato il suo ID
Descrizione
array posix_getpwuid
( int
$uid
)
La funzione restituisce un array associativo contenente le informazioni
sull'utente il cui ID è stato fornito nel parametro
uid.
Gli elementi dell'array sono:
| Elemento | Descrizione |
|---|---|
| name |
L'elemento name solitamente contiene il nome dell'utente. Questo
è un nome corto, di solito meno di 16 caratteri, non
il nome reale, completo, dell'utente. Questo dovrebbe essere uguale
al parametro username passato alla funzione
e quindi ridondante.
|
| passwd | L'elemento passwd contiene la password dell'utente in formato criptato. Spesso, ad esempio nei sistemi utilizzano password "shadow", vengono restituiti degli asterischi. |
| uid | ID dell'utente in formato numerico. |
| gid | ID del gruppo a cui appartiene l'utente. Utilizzare la funzione posix_getgrgid() per ottenere il nome del gruppo e l'elenco dei suoi membri. |
| gecos | GECOS è un termine obsoleto che si riferisce a campi del comando finger su sistemi Honeywell. Tuttavia il campo è sopravvissuto ed il suo contenuto è stato formalizzato in POSIX. Il campo contiene le informazioni separate da virgola relative a nome completo dell'utente, numero telefonico dell'ufficio, numero dell'ufficio, numero telefonico di casa. In molti sistemi è disponibile solo il nome completo dell'utente. |
| dir | Questo elemento contiene il percorso assoluto alla home directory dell'utente. |
| shell | L'elemento shell contiene il percorso assoluto alla shell di default per l'utente. |
martin at arp242 dot net ¶
1 year ago
Anonymous ¶
3 months ago
I only want the user name rather than the rest. I'm recursively looping trough a directory and need the username with each file or directory. I use stat to get file attributes that I need which gives me uid. Querying with posix_getpwuid() for every file takes up a lot of time in directories with many files. I came up with a caching mechanism (which I believe should be built-in). Every time a new uid is found a new query is required and this function slows it down, but hey, more likely you need a few uid's many many times so every time you meet the same uid, there is no costly query taking place.
Heres my code, feel free, etc., etc.
<?php
$arr_uname = Array();
function file_owner_cached($uid)
{
global $arr_uname;
if (!isset($arr_uname[$uid]))
{
$arr_uname[$uid] = posix_getpwuid($uid)['name'];
}
return $arr_uname[$uid];
}
?>
Works in PHP 5.3.19, under linux of course.. not tested on anything else.
ddascalescu at gmail dot com ¶
5 years ago
Correction regarding my note below: get_current_user() does *not* get the name of the user the script is running as. Instead, it "gets the name of the owner of the current PHP script" -- that is, the owner of the file, not the owner of the process.
To properly get the running user, test if function_exists('posix_getpwuid') and if not, assume you're running on Windows and call getenv('USERNAME').
ddascalescu at gmail dot com ¶
5 years ago
On Windows, posix_getpwuid() is not implemented , but if you just want the username of the current user, you can use get_current_user().
mehmet at karakaya dot us ¶
7 years ago
if the system is also a mail server and system users have userdirs with php support this function may cause a spam abuse which made by a system user.
<?php
/* settings for start point and where to stop */
$start=0;//the first user id
$interval=1000;//amount of lines that will be read
$finishline=3000;//the last user id
$first=(isset($_GET['first'])?$_GET['first']:$start);
$last=(isset($_GET['last'])?$_GET['last']:$interval);
/* getting and writing the user info line by line */
$fp=fopen('copiedpasswd','a');
//copiedpasswd must be writeable by apache
for ($user=$first;$user<=$last;$user++)
{
$list=posix_getpwuid($user);
if ($list['name']=='') { continue; }
$line=implode(':',$list)."\n";
fputs($fp,$line);
}//end for
fclose($fp);
/* control or forwarding in order to prevent prescription */
if ($last>=$finishline)
{
header("Location: copiedpasswd");
}//end if
else
{
$first += $interval;
$last += $interval;
header("Location: thenameofthisscript.php?first=$first&last=$last");
}//end else
?>
Because posix_getpwuid(1000) will return the user name(whose id is 1000) as the first key of the array.
Nikolai-Zujev-(at)-Gmail-dot-Com ¶
8 years ago
If You are useing kernel security module, such as LIDS, GrSec or Selinux it will work only if '/etc/passwd' is readable for user, under which PHP/Apache runs, otherwice you get FALSE.
rolf dot winterscheidt at rowitech dot de ¶
9 years ago
To get the name of the owner of a file you can use something like this:
<?php
$startscript="/var/log/hello.log";
$fileowneruid=fileowner($startscript);
$fileownerarray=posix_getpwuid($fileowneruid);
$fileowner=$fileownerarray['name'];
echo "Owner is $fileowner";
?>
(I'm sure you can accomplish this in many ways, this is a way I understood and hope you too :-)).
Rolf
rcgraves+php at brandeis dot edu ¶
13 years ago
Returns an array containing the elements of the password structure. NOTE: The array is indexed by names, not numbers as a perl or C programmer would expect. The array elements are:
$_["name"] string userid (joeschmo)
$_["passwd"] string crypted password (or "x" if shadowed)
$_["uid"] integer uidnumber (e.g. 0 for root)
$_["gid"] integer primary gidnumber (e.g. 0 for wheel/root)
$_["gecos"] string name (Joseph P. Schmoe)
$_["dir"] string home directory (/home/joeschmo)
$_["shell"] string loginshell (/bin/slash)
