Any text editor like NotePad or TexEdit should do as long as it saves strictly ASCII text and not add other stuff or save in another format (like Word).  I use UltraEdit myself.
You might want to close Poser while editing - it has this thing about locking files so that they cannot be updated while it's running.

C makes it easy to shoot yourself in the foot. C++ makes it harder, but when you do, you blow your whole leg off.

 -- Bjarne Stroustrup

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