Without getting into a lot of unnecessary detail, I'm working on a project
to allow PHP to communicate with a proprietary database.

The IPC mechanism I'm using is 'proc_open'; there is a server-side component
(written in C) that 'listens' for PHP requests (via its stdin) and spits out
the appropriate response (via its stdout). Conversely, the PHP side uses
fwrite() to send to the component's stdin and fread() to read from the
component's stdout.

Ok so far?

What happens is that there is a situation where the C component will send a
a string with an embedded chr(10) via stdout to PHP's stdin. On Windows this
is getting converted to chr(13).chr(10).

So the problem is that if I send a n byte string ( with an embedded chr(10)
) then fread() gets an n+1 byte string ( with the addition of the chr(13) ).

I've already tried using the 'binary_pipes' in the 'other_options' array.

I've also tried adding a 'b' as a 'pipe' option (see code below) but PHP
doesn't like it.

Here's simplified PHP code to illustrate the problem :

$descriptorspec = array(
0 => array("pipe", "r"),
1 => array("pipe", "w"), //tried doing "wb"
2 => array("pipe", "r"));

$process = proc_open('C:\sandbox\bin\cprog.exe', $descriptorspec, $pipes);

if (is_resource($process)) {
$rtnval = fread($pipes[1], 1024);

echo "$rtnval <br />"
echo strlen($rtnval)."<br /><br />";

$a = str_split($rtnval);
foreach ($a as $character) {
echo ord($character)."<br />";
}

fclose($pipes[0]);
fclose($pipes[1]);
fclose($pipes[2]);
proc_close($process);
}

If the C program sends the string 'LINE1'.chr(10).'LINE2' then PHP responds
with:

LINE1 LINE2
12

76
73
78
69
49
13 <---this is being added in by PHP
10
76
73
78
69
50


Is there some 'switch' that I can use to turn this off? Or am I going to
have to filter this out myself?

Daniel Klein

On Mon, 11 Feb 2008 14:50:54 -0500, Daniel Klein <danielk@featherbrain.net>
wrote:

Ok, I'm missing a ;. The line should read:

echo "$rtnval <br />";

That's what I get for changing the script in my newsreader instead of in my
IDE (phpDesigner, which would have caugth this pronto) :-(

***

Anyway, it's been 2 days with no response; does this mean that I have found
a 'buglet'?

Daniel Klein

On Wed, 13 Feb 2008 16:40:58 +0100, Daniel Klein
<danielk@featherbrain.net> wrote:

> On Mon, 11 Feb 2008 14:50:54 -0500, Daniel Klein
> <danielk@featherbrain.net>
> wrote:
>
> Ok, I'm missing a ;. The line should read:
>
> echo "$rtnval <br />";
>
> That's what I get for changing the script in my newsreader instead of in
> my
> IDE (phpDesigner, which would have caugth this pronto) :-(
>
> ***
>
> Anyway, it's been 2 days with no response; does this mean that I have
> found
> a 'buglet'?

Depends, I cannot find you original post on my nntp server, it doesn't
ring a bell, and you haven't quoted yourself, so I have no idea what
you're writing about. Care to restate the problem for me?
--
Rik Wasmus

On Wed, 13 Feb 2008 16:54:54 +0100, "Rik Wasmus"
<luiheidsgoeroe@hotmail.com> wrote:

>On Wed, 13 Feb 2008 16:40:58 +0100, Daniel Klein
><danielk@featherbrain.net> wrote:
>
>> On Mon, 11 Feb 2008 14:50:54 -0500, Daniel Klein
>> <danielk@featherbrain.net>
>> wrote:
>>
>> Ok, I'm missing a ;. The line should read:
>>
>> echo "$rtnval <br />";
>>
>> That's what I get for changing the script in my newsreader instead of in
>> my
>> IDE (phpDesigner, which would have caugth this pronto) :-(
>>
>> ***
>>
>> Anyway, it's been 2 days with no response; does this mean that I have
>> found
>> a 'buglet'?
>
>Depends, I cannot find you original post on my nntp server, it doesn't
>ring a bell, and you haven't quoted yourself, so I have no idea what
>you're writing about. Care to restate the problem for me?

Here's the original (corrected) post:

===============================================
Without getting into a lot of unnecessary detail, I'm working on a project
to allow PHP to communicate with a proprietary database.

The IPC mechanism I'm using is 'proc_open'; there is a server-side component
(written in C) that 'listens' for PHP requests (via its stdin) and spits out
the appropriate response (via its stdout). Conversely, the PHP side uses
fwrite() to send to the component's stdin and fread() to read from the
component's stdout.

Ok so far?

What happens is that there is a situation where the C component will send a
a string with an embedded chr(10) via stdout to PHP's stdin. On Windows this
is getting converted to chr(13).chr(10).

So the problem is that if I send a n byte string ( with an embedded chr(10)
) then fread() gets an n+1 byte string ( with the addition of the chr(13) ).

I've already tried using the 'binary_pipes' in the 'other_options' array.

I've also tried adding a 'b' as a 'pipe' option (see code below) but PHP
doesn't like it.

Here's simplified PHP code to illustrate the problem :

$descriptorspec = array(
0 => array("pipe", "r"),
1 => array("pipe", "w"), //tried doing "wb"
2 => array("pipe", "r"));

$process = proc_open('C:\sandbox\bin\cprog.exe', $descriptorspec, $pipes);

if (is_resource($process)) {
$rtnval = fread($pipes[1], 1024);

echo "$rtnval <br />";
echo strlen($rtnval)."<br /><br />";

$a = str_split($rtnval);
foreach ($a as $character) {
echo ord($character)."<br />";
}

fclose($pipes[0]);
fclose($pipes[1]);
fclose($pipes[2]);
proc_close($process);
}

If the C program sends the string 'LINE1'.chr(10).'LINE2' then PHP responds
with:

LINE1 LINE2
12

76
73
78
69
49
13 <---this is being added in by PHP
10
76
73
78
69
50


Is there some 'switch' that I can use to turn this off? Or am I going to
have to filter this out myself?
================================================== ==

Daniel Klein

On Wed, 13 Feb 2008 18:47:51 +0100, Daniel Klein
<danielk@featherbrain.net> wrote:
> Here's the original (corrected) post:
>
> ===============================================
> Without getting into a lot of unnecessary detail, I'm working on a
> project
> to allow PHP to communicate with a proprietary database.
>
> The IPC mechanism I'm using is 'proc_open'; there is a server-side
> component
> (written in C) that 'listens' for PHP requests (via its stdin) and spits
> out
> the appropriate response (via its stdout). Conversely, the PHP side uses
> fwrite() to send to the component's stdin and fread() to read from the
> component's stdout.
>
> Ok so far?
>
> What happens is that there is a situation where the C component will
> send a
> a string with an embedded chr(10) via stdout to PHP's stdin. On Windows
> this
> is getting converted to chr(13).chr(10).
>
> So the problem is that if I send a n byte string ( with an embedded
> chr(10)
> ) then fread() gets an n+1 byte string ( with the addition of the
> chr(13) ).
>
> I've already tried using the 'binary_pipes' in the 'other_options' array.

I assume you don't have PHP6, or did the secretly implement this allready?

> I've also tried adding a 'b' as a 'pipe' option (see code below) but PHP
> doesn't like it.
>
> Here's simplified PHP code to illustrate the problem :
>
> $descriptorspec = array(
> 0 => array("pipe", "r"),
> 1 => array("pipe", "w"), //tried doing "wb"
> 2 => array("pipe", "r"));

Shouldn't STDERR be 'w'?


> $process = proc_open('C:\sandbox\bin\cprog.exe', $descriptorspec,
> $pipes);
>
> if (is_resource($process)) {
> $rtnval = fread($pipes[1], 1024);
> $a = str_split($rtnval);
> foreach ($a as $character) {
> echo ord($character)."<br />";
> }
> }
>
> If the C program sends the string 'LINE1'.chr(10).'LINE2' then PHP
> responds
> with:
>

> 76
> 73
> 78
> 69
> 49
> 13 <---this is being added in by PHP
> 10

> Is there some 'switch' that I can use to turn this off? Or am I going to
> have to filter this out myself?

Hmmz, I tried this under windows:
'program with output' test.php:
<?php
echo "foo\nbar\n";
?>
Actual code:
<?php
$h = proc_open('C:\PHP\php.exe
G:\Personal\echo.php',array(0=>array('pipe','r'),1 =>array('pipe','w'),2=>array('pipe','w')),$pipes) ;
//,NULL,NULL,array('bypass_shell',true)); <- tried, not needed
if (is_resource($h)) {
$rtnval = fread($pipes[1], 1024);
echo "$rtnval \n";
echo strlen($rtnval)."\n\n";

$a = str_split($rtnval);
foreach ($a as $character) {
echo ord($character)."\n";
}

fclose($pipes[0]);
fclose($pipes[1]);
fclose($pipes[2]);
proc_close($h);
}
?>
Output:
foo
bar

8

102
111
111
10
98
97
114
10

So, it's your C(++?) program. See for instance
<http://www.velocityreviews.com/forums/t281073-tricky-cout-with-0x0a-value.html>.
Make sure you output in binary instead of text mode, or oh so convenient
translation is done for you...
--
Rik Wasmus