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Allowing for an input file

Allowing for an input file

Allowing for an input file

I have a Fortran program that allows an input file to be defined on execution, as well as an output file...

CODE -->

.extracks <filein.lst >fileout.trk 

I am running this on my Mac and on a Windows system.

The output part (>) works fine but I cannot use the input declaration (<).

How do I do this on the commandline to achieve the required result?

RE: Allowing for an input file

You say, your program allows an input file to be defined on execution but you cannot use input redirection with "<".
What happens when you try to use only "<" like this ?


extracks < filein.lst 

It could have several reasons:
- Maybe your program tries to read a file with a specific name and you can then use only output redirection
- Or your input file is not in a format as the program expected: For example it expect two integer numbers M and N in the first line and then it expects another M rows with N columns each of floating point numbers

The reason why it doesn't work is not apparent without seeing the program source file.

RE: Allowing for an input file

It turns out that my choice of command line operations (PowerShell) is the cause; it reserves < for potential future usage.

If I had stuck to the good old command prompt, I would never have encountered the issue.

It also transpires that I probably don’t need to use the program anyway. It creates chart data that I can use to generate a Herschel-Russell Diagram; but I can just as easily use IDL to create the graph from the raw data I get from my Fortran simulation program that IS working! Hahaha!

Thank you for your help. :)

RE: Allowing for an input file

You wrote, that you are running this on the Mac and on a Windows system, so I thought that the issue with the redirection is on the both systems.
But thanks for the sharing your experience with power shell redirection. Until now I have never used Powershell instead of the windows default command prompt. I only used it to run a self-written Powershell scripts. But it wouldn't even occur to me in a dream that the redirection operators, that are common in all shells, would not work as expected in PowerShell smile

Here I found
that this is how it should be used in Powershell


Get-Content filein.lst | ./extracks > fileout.trk 

RE: Allowing for an input file

Yes, sorry. I have tried running it on both systems. This particular issue arose on my Windows system, and I incorrectly connected the failed attempt on both as the same cause - evidence of a failing memory.
The Mac issue was not a failure of code but of what I got out the other side of the program!
Shows I’m working too hard! Hahaha.

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