an exe can be executed from cmd but wraping into perl fail to run

kaka_2 has asked for the wisdom of the Perl Monks concerning the following question:

Hello Experts,

I have an application exe which run quite well from the cmd but when put it into thr simple perl file it does not return any output.

$a = `command.exe`;
print $a;
[download]

Question is how to troubleshoot? what make it different when it is being executed from a perl file and not cmd.

any hint in this regard will be helpful.

Thank You. -KAKA-

Comment on an exe can be executed from cmd but wraping into perl fail to run Download Code

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Re: an exe can be executed from cmd but wraping into perl fail to run by Anonymous Monk on Dec 16, 2014 at 17:21 UTC
To see if your command is failing or exiting with a nonzero code, which usually indicates an error, try inspecting `$?` and `$!`. Or, even better, use IPC::System::Simple's `capture`, since that does the interpretation of `$?` for you.	[reply] [d/l] [select]
Re^2: an exe can be executed from cmd but wraping into perl fail to run by kaka_2 (Sexton) on Dec 17, 2014 at 11:28 UTC
$? prints 0 and $! prints nothing.	[reply]
Re^3: an exe can be executed from cmd but wraping into perl fail to run by Anonymous Monk on Dec 17, 2014 at 11:49 UTC
That's strange, but we'll need more information to help debug. Please provide code, sample output, anything else you can think of, see also How do I post a question effectively? Did you try the suggestion of using `capture` from IPC::System::Simple? Also, try using `capture` from Capture::Tiny, because that also captures `STDERR`.	[reply] [d/l] [select]
Re^4: an exe can be executed from cmd but wraping into perl fail to run by kaka_2 (Sexton) on Dec 17, 2014 at 14:04 UTC
Re: an exe can be executed from cmd but wraping into perl fail to run by RichardK (Parson) on Dec 16, 2014 at 17:23 UTC
print out the error code $? and see what you get. or use system	[reply]
Re: an exe can be executed from cmd but wraping into perl fail to run by Laurent_R (Canon) on Dec 16, 2014 at 18:29 UTC
You did not say much about your executable application, so we don't know what it's doing. It could be that it is sending its output to STDERR instead of STDOUT, in which case you would not capture such output with the backticks. Also please tell us on which operating system you are doing that.	[reply]
Re: an exe can be executed from cmd but wraping into perl fail to run by soonix (Canon) on Dec 18, 2014 at 08:15 UTC
Maybe the perl application changes the `PATH` or the working directory. You could find this out by trying the commands print `dir`; print `set`; [download] If that's the case, you have to give the full path of your exe, e.g. $a = `C:\\where\\ever\\it\\is\\command.exe`; [download]	[reply] [d/l] [select]


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