Posted by Jerry Stuckle on 03/11/07 18:34

John C. Frickson wrote:
>
>
> On 2007-03-11 07:48, Jerry Stuckle wrote:
>> John C. Frickson wrote:
>>>
>>>
>>> On 2007-03-09 20:41, Jerry Stuckle wrote:
>>>> John C. Frickson wrote:
>>>>> On 2007-03-09 10:28, John C. Frickson wrote:
>>>>>> My company produces reports for our customers in PDF format. I have a
>>>>>> php script that verifies login status and access rights, and sends
>>>>>> the pdf to the client using readfile().
>>>>>>
>>>>>> This has worked fine until recently. One of our customers' reports
>>>>>> is 10.6MB, and the customer never receives it and I can't get it
>>>>>> either. I checked the Apache access_log, and it shows varying
>>>>>> amounts of bytes being sent, but always close to 10MB.
>>>>>>
>>>>>> I tried changing the php script to do fopen(), fread(), echo,
>>>>>> ob_flush() and flush(). After each flush, I write a message to a log
>>>>>> file. The messages in the log file stop at 10MB, as if the php script
>>>>>> is hung.
>>>>>>
>>>>>> Using a network monitor, I see the connection being established, the
>>>>>> HTTP GET being sent, but no content coming back.
>>>>>>
>>>>>> PHP version is 5.1.2
>>>>>> Apache is 2.2.3
>>>>>> OS is SuSE Linux Enterprise Server 10.0 - 64bit
>>>>>>
>>>>>> Current test version looks like this:
>>>>>>
>>>>>> ini_set("output_buffering", "0");
>>>>>> ini_set("implicit_flush", "1");
>>>>>> ini_set("memory_limit", "100M");
>>>>>> ini_set("max_execution_time", "600");
>>>>>> $lth = 0;
>>>>>> $in = fopen($path, "r");
>>>>>> while (!feof($in)) {
>>>>>> $data = fread($in, 8192);
>>>>>> $lth += strlen($data);
>>>>>> $errLog->WriteLog("Read $lth bytes" , "debug.txt");
>>>>>> echo $data;
>>>>>> $errLog->WriteLog("After echo" , "debug.txt");
>>>>>> ob_flush();
>>>>>> $errLog->WriteLog("After ob_flush" , "debug.txt");
>>>>>> flush();
>>>>>> $errLog->WriteLog("After flush" , "debug.txt");
>>>>>> }
>>>>>> $errLog->WriteLog("Got EOF", "debug.txt");
>>>>>> fclose($in);
>>>>>> $errLog->WriteLog("End of Script - read $lth bytes", "debug.txt");
>>>>>>
>>>>>>
>>>>>> The last five lines of the debug.txt log file say:
>>>>>>
>>>>>> Read 10223616 bytes
>>>>>> After echo
>>>>>> After ob_flush
>>>>>> After flush
>>>>>> Read 10231808 bytes
>>>>>> After echo
>>>>>>
>>>>>> So it's never returning from the ob_flush() call. Time from first
>>>>>> log entry to last is about 1 second.
>>>>>>
>>>>>> Any ideas?
>>>>>> John
>>>>>
>>>>> I noticed I didn't have a "Content-Length" header, so I added it
>>>>> and it's now working. Even without the header, it should have
>>>>> worked anyway, shouldn't it?
>>>>
>>>> Not reliably. There is a reason for the Content-Length header - to
>>>> let the browser know how much to expect.
>>>>
>>>> Without the header the browser is free to figure on it's own how
>>>> long the data should be (no browser I know of allows "unlimited
>>>> length). And evidently you finally exceeded the browser default.
>>>>
>>>
>>> Except NO data ever got sent to the browser. So it's something in
>>> either PHP or Apache that decided to quit. True, I wrote bad code
>>> by forgetting the Content-Length header, but it's a bit disturbing
>>> that PHP or Apache just didn't send any data without any kind of
>>> warning or error message.
>>
>> What's in your Apache error log?
>>
>> Or, if you are logging PHP errors to a separate log file (unusual, but
>> possible - check phpinfo()), what's in it?
>>
>> And if there is such a severe error that PHP/Apache can't send your
>> data to the browser, it probably can't send an error message, either.
>> But it will log something.
>>
>
> Nothing in the Apache error log (where PHP errors usually go).
> The Apache access log shows a "200" response code and a short
> number of bytes (such as 10343101 when it should be 11500016).
>
> I'm cross-posting this to a couple other groups that might be
> relevant.

In that case data WAS sent to the browser. But since it was incomplete
it looks like the browser just didn't display anything.

That's not unusual.

--
==================
Remove the "x" from my email address
Jerry Stuckle
JDS Computer Training Corp.
jstucklex@attglobal.net
==================

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