Running External Program - getting the programs results not just the stdout

General Usage
1

Hi,

I have managed to confuse myself but I am sure there is a simple answer.
I have a c++ script I can call this in the terminal with:

./script $InputFile > $OutputFilePathAndName

With the terminal printing the stdout but also saving the c++ programs results to the file described in OutputFilePathAndName
In Julia if I write something like:

TerminalLine="./script $InputFile > $OutputFilePathAndName"
TerminalLine=split("$TerminalLine")
run(`$TerminalLine`);

The file OutputFilePathAndName never writes? In a simple terminal this writes correctly but not using Julia ā€˜runā€™ or Julias shell.
In windows I got around this using:

TerminalLine="./script $InputFile > $OutputFilePathAndName"
TerminalLine=split("powershell $TerminalLine")
run(`$TerminalLine`);

i.e. calling powershell as a subprocess.
Any ideas what I need to do in Linux?

Cheers,
Tim

2

I think this might be right for you:

pipeline(`do_work`, stdout=pipeline(`sort`, "out.txt"))

That way it should be possible to pipe the output of the program where you want it.

3

No, I thought this might be too and tried this earlier. This just returns the terminal output in the text file, not the output from the program. I run this as so:

run(pipeline(`./script`,stdout=pipeline(`sort`,"$OutputFilePathAndName"))  );
4

I think you donā€™t need the sort or the second pipeline here, that is just from the example in the documentation. I also assume that OutputFilePathAndName is a string so "$OutputFilePathAndName" == OutputFilePathAndName

But Iā€™m a little confused. If you call just the program from the shell, isnā€™t all output shown there? If so, the stdout parameter should catch that. If not, where is it going instead? What is the difference between ā€œterminal outputā€ and ā€œoutput from the programā€?

5

I have spotted a mistake in my code.Your answer made me go back and double check this (and it works).
Cheers for the advice.
Tim

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