|  support |  documentation |  report a bug |  advanced search |  search howto |  statistics |  random bug |  login
Bug #21815 Buffer loss with fpassthru on popen
Submitted: 2003-01-22 04:01 UTC Modified: 2003-02-12 19:26 UTC
From: stefan at fostam dot franken dot de Assigned: wez
Status: Closed Package: Filesystem function related
PHP Version: 4.3.0 OS: Linux 2.4
Private report: No CVE-ID:
 [2003-01-22 04:01 UTC] stefan at fostam dot franken dot de
When calling fpassthru() on a file pointer opened with popen(), it fails if there has been already read from that pointer.

$fp = popen("/bin/ls /", "r");
if ($fp) {
  $line = fgets($fp, 1024);
  print $line;


Results in the following error:
fpassthru(): 77 bytes of buffered data lost during conversion to FILE*!

The same script works fine with php 4.2.3. It also works fine if there hasn't been read from the file before (i.e. omitting the fgets() line in above example).


Add a Patch

Pull Requests

Add a Pull Request


AllCommentsChangesGit/SVN commitsRelated reports
 [2003-01-22 04:53 UTC]
I know what the problem is -> assigning to myself
 [2003-02-12 19:26 UTC]
This bug has been fixed in CVS.

In case this was a PHP problem, snapshots of the sources are packaged
every three hours; this change will be in the next snapshot. You can
grab the snapshot at
In case this was a documentation problem, the fix will show up soon at

In case this was a website problem, the change will show
up on the site and on the mirror sites in short time.
Thank you for the report, and for helping us make PHP better.

Fix will be in PHP 4.3.1, due soon.
PHP Copyright © 2001-2015 The PHP Group
All rights reserved.
Last updated: Wed Nov 25 08:01:54 2015 UTC