>From the cygwin API faq info:
When processing in text mode, certain values of data are treated
specially. A \n (new line, NL) written to the file will prepend a \r
(carriage return, CR) so that if you `printf("Hello\n") you in fact
get "Hello\r\n". Upon reading this combination, the \r is removed and
the number of bytes returned by the read is 1 less than was actually
read. This tends to confuse programs dependent on ftell() and fseek().
A Ctrl-Z encountered while reading a file sets the End Of File flags
even though it truly isn't the end of file.
That means if the binary data being piped
through to gnuplot contains a Ctrl-Z then the
pipe will treat it as end-of-file. Is there a
way to check if that is happening.
At any rate, the solution would be to
use binmode for the pipe.
--Chris
On Tue, Feb 12, 2013 at 11:15 AM, Chris Marshall <[email protected]> wrote:
> Looking at the docs for IPC::Open3, I see the
> warning:
>
> If you try to read from the child's stdout writer
> and their stderr writer, you'll have problems with
> blocking, which means you'll want to use select()
> or the IO::Select, which means you'd best use
> sysread() instead of readline() for normal stuff.
>
> and I notice in the open3() call that you have
> both $err opened to child STDOUT and STDERR.
> Maybe that is triggering the problem.
>
> Would it be possible to redirect STDERR to
> STDOUT and then just open the one?
>
> --Chris
>
> On Tue, Feb 12, 2013 at 11:05 AM, Chris Marshall <[email protected]>
> wrote:
>> Still hangs. My guess is a problem with binary
>> data. I could not see where the input handle
>> was opened and had binmode set. Is there a
>> way to force ascii mode so I could at least
>> see if that is the source of the problem?
>>
>> --Chris
>>
>> On Tue, Feb 12, 2013 at 10:17 AM, Craig DeForest
>> <[email protected]> wrote:
>>> Hi, Chris,
>>>
>>> Thanks very much for giving this another look!
>>>
>>> Your image example definitely found a bug. The long delay does not happen
>>> for me under either Linux or MacOS. I suspect that there might a problem
>>> with Cygwin IPC that needs to be worked around - the pipe seems to be
>>> hanging up for some reason.
>>>
>>> As a simple test case, why not try
>>>
>>> PDL::Graphics::Gnuplot::image(rvals(5,5))
>>>
>>> which should produce something very quickly? If *that* doesn't work, then
>>> we need to get someone with a Cygwin system and an afternoon to try to
>>> understand why it is failing. I could do that except for the part about
>>> having a Cygwin system. Would you be willing to let me ssh into your
>>> virtual machine some time?
>>>
>>> Cheers,
>>> Craig
>>>
>>>
>>>
>>> On Feb 12, 2013, at 8:04 AM, Chris Marshall <[email protected]> wrote:
>>>
>>>> Hi Craig-
>>>>
>>>> I'm trying again with the PDL::Graphics::Gnuplot on
>>>> my cygwin/win7 system to sort things out before the
>>>> coming PDL-2.4.12 release.
>>>>
>>>> Starting with the tutorial on the wiki, I have a
>>>> few questions/observations:
>>>>
>>>> - the terminal type seems to need quotes, 'png'
>>>> - how can I list terminal types from perl
>>>> - the default empty string gives terminal type ''
>>>> (this breaks the mouse click examples saying
>>>> that '' terminal does not support it---even though
>>>> the default for my system is 'x11'
>>>> - reading mouse on 'x11' gave no $status hash
>>>>
>>>> Finally, I got a window open and displaying ok,
>>>> so I tried to display an image. Boom! This is
>>>> a bit disheartening since the image was small
>>>> and doing images with plot overlays is specifically
>>>> what I need (often) to comprehend image data.
>>>>
>>>> I'm hoping it is a bug somewhere that can be
>>>> fixed. Here is the output from my pdl2
>>>> session. The image is a shape [3,320,80]
>>>> float piddle with pixels in [0,1] and badvalues.
>>>>
>>>> pdl> use PDL::Graphics::Gnuplot
>>>> pdl> $hsv40 = get_hsv_frame(40);
>>>> Loading get_hsv_frame.pdl ...found ./crank/get_hsv_frame.pdl
>>>> pdl> PDL::Graphics::Gnuplot::image( {cbrange=>[0,1]}, $hsv40->mv(0,-1)
>>>> )
>>>> Runtime error: Hmmm, my main Gnuplot process didn't respond for 60 seconds.
>>>> This could be a bug in PDL::Graphics::Gnuplot or gnuplot itself --
>>>> although for some terminals (like x11) it could be because of a
>>>> slow network. If you don't think it is a network problem, please
>>>> report it as a PDL::Graphics::Gnuplot bug. You might be able to
>>>> ignore this message, or you might have to restart() the object.
>>>> If you are getting this message spuriously, you might like to
>>>> set the "wait" terminal option to a longer value (in seconds).
>>>> at /cygdrive/f/perl/local/lib/perl5/PDL/Graphics/Gnuplot.pm line 6030.
>>>>
>>>> PDL::Graphics::Gnuplot::_checkpoint('PDL::Graphics::Gnuplot=HASH(0x820c3e48)',
>>>> 'main', 'HASH(0x82098438)') called at
>>>> /cygdrive/f/perl/local/lib/perl5/PDL/Graphics/Gnuplot.pm line 2462
>>>> PDL::Graphics::Gnuplot::plot(undef, undef,
>>>> 'PDL=SCALAR(0x820bdcb0)') called at
>>>> /cygdrive/f/perl/local/lib/perl5/PDL/Graphics/Gnuplot.pm line 3098
>>>> PDL::Graphics::Gnuplot::image('HASH(0x825d8bb0)',
>>>> 'PDL=SCALAR(0x820bdcb0)') called at (eval 466) line 5
>>>> pdl> PDL::Graphics::Gnuplot::image( {cbrange=>[0,1]},
>>>> $hsv40->mv(0,-1)->setbadtoval(0) )
>>>> Runtime error: Hmmm, my main Gnuplot process didn't respond for 60 seconds.
>>>> This could be a bug in PDL::Graphics::Gnuplot or gnuplot itself --
>>>> although for some terminals (like x11) it could be because of a
>>>> slow network. If you don't think it is a network problem, please
>>>> report it as a PDL::Graphics::Gnuplot bug. You might be able to
>>>> ignore this message, or you might have to restart() the object.
>>>> If you are getting this message spuriously, you might like to
>>>> set the "wait" terminal option to a longer value (in seconds).
>>>> at /cygdrive/f/perl/local/lib/perl5/PDL/Graphics/Gnuplot.pm line 6030.
>>>>
>>>> PDL::Graphics::Gnuplot::_checkpoint('PDL::Graphics::Gnuplot=HASH(0x820c3e48)',
>>>> 'main', 'HASH(0x825c60c0)') called at
>>>> /cygdrive/f/perl/local/lib/perl5/PDL/Graphics/Gnuplot.pm line 2389
>>>> PDL::Graphics::Gnuplot::plot(undef, undef,
>>>> 'PDL=SCALAR(0x825ccb28)') called at
>>>> /cygdrive/f/perl/local/lib/perl5/PDL/Graphics/Gnuplot.pm line 3098
>>>> PDL::Graphics::Gnuplot::image('HASH(0x8210deb0)',
>>>> 'PDL=SCALAR(0x825ccb28)') called at (eval 475) line 5
>>>>
>>>> Hope this gives you some ideas. Do you have
>>>> a working image example that I could try?
>>>>
>>>> Thanks,
>>>> Chris
>>>>
>>>
_______________________________________________
Perldl mailing list
[email protected]
http://mailman.jach.hawaii.edu/mailman/listinfo/perldl
