PHP exec( ) problems!

Posted on 2003-02-27
Medium Priority
Last Modified: 2006-11-17
Hi all

When I use the exec() call on my Windows 2000 box
in the following form:

exec("command 2>&1",$results);

it works perfectly.  Even if "command" is an incorrect command string $results, as you would expect, will contain the error (ie. Bad command or file name).  But when I use the same structure on Windows 98 only successful "simple" commands work. Nothing is returned at all when there is an error, the $results array is always empty.  This is a problem as I am processing a XML validation using LIBXML and I am interested in finding if there are any errors.    

In the exec call listed above the additional string "2>&1" is supposed to redirect error output to the standard console output.  It doesn't seem that this works in the DOS on 98, is there any way I can return errors to the $results array.

Your help is much appreciated


Question by:kevadooch
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Expert Comment

ID: 8032750
all I can say is that I avoid it because in the doc it says "exec() may not work on Windows platform"

Expert Comment

ID: 8033259
The shell processor on W98 is nothing like the one on NT based systems (like WNT, W2000, WXP).  You might ask in the "operating systems" experts area under W98 how to get the errors to go to stdout and then use that in your exec on W98.

Author Comment

ID: 8033338
Unfortunately at this time the only way that one can validate an XML document against a DTD is to use a command line application.  So I'm pretty much reliant on using exec().

A side note is that I have found out that it is pretty much impossible to redirect error output to standard output in Win 98 using the trusty "2>&1" string.  
As the exec() command returns the standard output I'm stumped.  Ahh well, I'll just have to put Windows 2000 or Linux down as a requirement  ...

.. unless anyone knows of a trick of hack to get round this


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LVL 15

Expert Comment

ID: 8033584
have you tried syntax > c:\textfile.txt and reading that file afterwards ?

Author Comment

ID: 8042728
I have been offered a solution by another expert.
You can use a program called "stderr" to merge the
standrad output streams.  This works a treat!!

Accepted Solution

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