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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 (profile)
Status: Closed Package: Filesystem function related
PHP Version: 4.3.0 OS: Linux 2.4
Private report: No CVE-ID: None
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From: stefan at fostam dot franken dot de
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 [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).


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 [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.

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