You'll need to ensure that the output buffer gets flushed. Try:

use IO::Handle;

open SYS,"| windows_exe_file.exe" or die ...;

SYS->autoflush(1);

print SYS "EXPORT this and that to thisFile.dat";
print SYS "\e";
close SYS;

my @data = do{ open IN, 'thisFile,dat'; local $/; <IN> };

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With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'
Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.

The start of some sanity?

In reply to Re^3: execute a file, then send terminate command? by BrowserUk
in thread execute a file, then send terminate command? by perlpreben

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