Running exec command php - php

Question

I have just installed pdf2htmlEX without any issues. If I run the command on the server it works fine. So I know the library itself is doing what it is supposed to do. If I run the command in php via the exec function nothing happens. I assume exec is used in this instance??
In PHP
// doesn't work
$output = exec('pdf2htmlEX --zoom 1.3 pdf/test.pdf');
// doesn't work
$output = shell_exec('pdf2htmlEX --zoom 1.3 pdf/test.pdf');
If I run a general command in the exec function it works fine, so I know exec is enabled and working as expected.
// works fine
$exec = exec('pwd', $output);
print_r($output);
Direct on Command Line not in PHP
// works and generates the file as expected.
pdf2htmlEX --zoom 1.3 pdf/test.pdf
Any help would be greatly appreciated.
Command line reference for library
https://github.com/coolwanglu/pdf2htmlEX/wiki/Quick-Start
EDIT:
After some further digging, it could be that the php script runs as a different user to the command line. My question would then be how do I check/fix this?

Answer 1

You just have to add the output html path and file name in your command :
Most of pdf_to_something packages usage with exec() is package_name [options] <input-filename> <output-filename>
$path = 'path/to/your/folder/';
$command = 'pdf2htmlEX '.$path.'test.pdf '.$path.'test.html';
exec($command);

Answer 2

Try following and check if your file is created in working directory.
exec('pdf2htmlEX --zoom 1.3 pdf/test.pdf',$output);

Answer 3

pdf2htmlEX doesn't output anything.
$cmd= "pdf2htmlEX --zoom 1.3 test/test.pdf";
exec($cmd, $output);
Will create a test.html file in the current directory.
Are you expecting something else?
Note: i've tested this on ubuntu by installing pdf2htmlEX with
sudo apt-get install pdf2htmlex
To get the output,
$a = file_get_contents("test.html");
echo $a;