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Re: using wshell.exec causes lockup while reading the output - what to do ?

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JJ,

> That's the main problem I've been trying to tell you. TextStream
> simply isn't capable enough when the stream is a standard handle
> which is a character device

So, I /can't/ check if its empty, I /can't/ ask how full it is, and its 
"read data" methods are all blocking ones.

The only way "exec" with output capturing can work is either with having 
just a single stream (on which the "readall" method would probably work), or 
when having two streams that /both/ emit lines of data (so that the 
"readline" method can be used), with both lines being shorter than a buffers 
worth.

That strongly limits the "exec" methods use cases.

Wait ... Nope, having both emit lines will still cause deadlocks.  Just 
imagine one stream getting shorter lines than the other.  As you can't empty 
a stream (trying to do so will cause a blocking situation) and you can't 
skip reading a stream when it doesn't have any data (checking for that also 
blocks), the buffer getting the longer lines will eventually fill up and 
block.

I really start to hate MS.   :-(

> I'm guessing that you also need to inspect the outputted data
> right away, instead of waiting until the program has terminated?

The stderr emits a progress counter for the screen (output count and a CR, 
the new value overwriting the last), stdout is supposed to be written to a 
file.

> There's that limit, yes. But it's not what causing TextStream to
> get stuck.

I think I understood the bit about blocking reads.  The buffersize problem 
goes, when using the "readline" method, ontop of that.   Or did I mis 
something ?

Regards,
Rudy Wieser

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using wshell.exec causes lockup while reading the output - what to do ? "R.Wieser" <address@not.available> - 2020-06-17 14:32 +0200
  Re: using wshell.exec causes lockup while reading the output - what to do ? "Mayayana" <mayayana@invalid.nospam> - 2020-06-17 08:48 -0400
  Re: using wshell.exec causes lockup while reading the output - what to do ? JJ <jj4public@vfemail.net> - 2020-06-17 22:12 +0700
    Re: using wshell.exec causes lockup while reading the output - what to do ? "R.Wieser" <address@not.available> - 2020-06-17 18:51 +0200
      Re: using wshell.exec causes lockup while reading the output - what to do ? JJ <jj4public@vfemail.net> - 2020-06-18 19:42 +0700
        Re: using wshell.exec causes lockup while reading the output - what to do ? "R.Wieser" <address@not.available> - 2020-06-18 17:26 +0200
          Re: using wshell.exec causes lockup while reading the output - what to do ? JJ <jj4public@vfemail.net> - 2020-06-19 21:16 +0700
            Re: using wshell.exec causes lockup while reading the output - what to do ? "R.Wieser" <address@not.available> - 2020-06-19 19:08 +0200
              Re: using wshell.exec causes lockup while reading the output - what to do ? JJ <jj4public@vfemail.net> - 2020-06-20 22:40 +0700
                Re: using wshell.exec causes lockup while reading the output - what to do ? "R.Wieser" <address@not.available> - 2020-06-20 18:56 +0200
                Re: using wshell.exec causes lockup while reading the output - what to do ? JJ <jj4public@vfemail.net> - 2020-06-21 12:33 +0700
                Re: using wshell.exec causes lockup while reading the output - what to do ? "R.Wieser" <address@not.available> - 2020-06-21 08:53 +0200
                Re: using wshell.exec causes lockup while reading the output - what to do ? JJ <jj4public@vfemail.net> - 2020-06-21 20:58 +0700
                Re: using wshell.exec causes lockup while reading the output - what to do ? "R.Wieser" <address@not.available> - 2020-06-21 17:46 +0200

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