Re: Using Perl on Cygwin; how to prevent display of unwanted usage/error message?

[Kenneth Wolcott <kennethwolcott@gmail.com>]

> On Fri, Jan 22, 2016 at 6:21 PM, Kenneth Wolcott
> <kennethwolcott@gmail.com> wrote:
>> Hi;
>>
>>   I'm using a qx call to "net user username /DOMAIN" (probably should
>> use system instead) to determine whether a person having an active
>> account in an application is still an employee.
>>
>>   I get two messages back (error and/or usage) when a username is not found.
>>
>> "The user name could not be found."
>>
>> and
>>
>> "More help is available by typing NET HELPMSG 2221."
>>
>> I'd like to hide (not display, not print) these two messages.
>>
>> Coming from a UNIX/Linux background, I'd do a "2>&1 > /dev/null"
>> operation to dispose of STDOUT and STDERR, but "1<&2 > NUL" (suggested
>> by
>>
>> "https://www.microsoft.com/resources/documentation/windows/xp/all/proddocs/en-us/redirection.mspx?mfr=true"
>>
>> does not seem to work.
>>
>>   I tried file descriptor 3, but that resulted in an error regarding
>> unsupported file handle,. or something like that.
>>
>>   I was considering using IPC::Run3, but I don't think that will help
>> with suppressing error message and usage message.
>>
>> Perhaps there is a Perl module that is native to Cygwin that will
>> perform this kind of lookup for me?  Maybe a Perl module that is NOT
>> native to Cygwin?
>>
>> Thanks,
>> Ken Wolcott
>>

On Fri, Jan 22, 2016 at 3:34 PM, Erik Soderquist
<ErikSoderquist@gmail.com> wrote:
> In cygwin, I use >/dev/null 2>&1 quite frequently and it works as expected.
>
> In windows cmd.exe, I don't know why they would recommend the < part
> for dealing with output, but I have used >NUL 2>&1 for the same effect
> in Windows command shells.
>
> -- Erik

Hi Erik;

  Thank you!  ">/dev/null 2>&1" solved the problem of hiding the
information I did not want displayed.

Thanks,
Ken

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