Not sure if this will help or not, but I had a similar problem a few years ago. On that occasion the progress message included a reference to a filename supplied via the command line. I discovered that by supplying a filename with a whole bunch of trailing spaces, it didn't affect the programs ability to open the file, but when it displayed the message it incorporated the trailing spaces. By adding enough spaces, it cause the pipe buffer to fill and so be output.

It doesn't look from your example that any of the parameters are paths, but if any of them are displayed as part of the progress message, you might try something like: 

$data1 = sprintf "./myC.exe 10 10 1 \"abc%s\"", ' ' x 4096;

[download]

or even, if the executable name is part of the message: 

$data1 = sprintf "%smyC.exe 10 10 1 abc", './' x 2048;

[download]
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In reply to Re: Pipe Problem by BrowserUk
in thread Pipe Problem by Anonymous Monk

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