Unix tools always work. Even when Windows ones don’t



In the video above, you can see, that we cannot drag and drop a file onto a PowerShell script. Conversely, we can easily do this with bash script having installed Git for Windows.

I needed to perform some trivial conversion within a SQL script, i.e. replace ROLLBACK with COMMIT. I thought I would implement it with PowerShell. I am not going to comment on the implementation itself, even though it turned out to be not that obvious. Then I realized, it would be nice, if I could drag and drop a file in question to apply the conversions on it.

This does not work with default configuration of PowerShell. I did not have time to hack it somewhere in the registry, as I assume it is doable. I switched to old, good bash shell instead.

It’s a pity I couldn’t do that with Windows native scripting technology. It is very interesting, that MinGW port of shell has been so carefully implemented, that even dragging and dropping works in non-native environment.

I recall the book Pragmatic Programmer: From Journeyman To Master. There is a whole subchapter about the power of Unix tools. The conclusion was, that over time we would come across plenty of distinguished file formats and tools to manipulate data stored with them. Some of them may become forgotten and abandoned years later, making it difficult to extract or modify the data. Some may work only on specific platforms.

But standard Unix tools like shell scripting, Perl, AWK will always exist. I should say: not only will they always exist, but also they will thrive and support almost every platform you can imagine. They work on plain text, which is easy to process. I am a strong proponent of before-mentioned technologies and I have successfully used them many times in everyday work. It sounds particularly strange among .NET developers, but this what it looks like. The PowerShell simply did not do the trick for me. Perl did. As it always does.

For the sake of the future reference I am including the actual scripts:

PowerShell script:

if (!$args[0])
{
  Write-Host "Please provide target file"
  pause
  exit 1
}

(gc -raw $args[0]) -replace "`nROLLBACK;", "`nCOMMIT;" | sc $args[0]

Bash script running Perl:

#!/bin/sh
perl -pi -w -e 's/^ROLLBACK;/COMMIT;/g;' "$1"

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