$MSYSTEM variable in bashrc

NOTE

I am using Windows 7. On installing msysgit and GitHub for Windows, I found that git bash can be called from the folders. I opened up the terminal and first thing I wanted was to change how it displays in the console.

Here is what echo $PS1 gave me:

\[\033]0;$MSYSTEM:\w\007 \033[32m\]\u@\h \[\033[33m\w$(__git_ps1)\033[0m\] $ 

I've been modifying my bash's PS1 for some time now, and know most of the content there is. But I have never ever seen $MSYSTEM before.

Google resulted in nothing except some results about using it to set $MSYSTEM=MINGW32 which of course isn't the case here.

So, what does MSYSTEM variable do? Also, when I create a file .bashrc and put this line there; the terminal now shows a blank-space just before my username. This is because of the empty space in this segment \007 \033 but it was absent before. Here are the screenshots when I use a custom .bashrc and when I don't:

_{Without bashrc}

_{With bashrc}

I know why the newline is absent from my customized terminal; but the questions are:

• What is $MSYSTEM?
• Why is the first blank-space space missing in first case?

It sets the Window title to the value of MSYSTEM variable. As far as the space, it looks like you messed up the final newline, notice carefully

export PS1='\[\033]0;$MSYSTEM:\w\007
\033[32m\]\u@\h \[\033[33m\w\033[0m\]
$ '

in the variable above each start of a new line insert a literal newline character into the PS1.

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