how to modify a file and how to read the path variable

i need to read out the path variable and then i´ve to write this in an bat-file. maybe someone can help me.

How's this?

ReadEnvStr $0 "Path"

FileOpen $1 "$EXEDIR\test.bat" w

FileWrite $1 "@Echo Off$\r$\nEcho $0$\r$\nPause"

FileClose $1

Yields a file called test.bat in the EXE directory which contains:

@Echo Off
Echo C:\WINDOWS\system32;C:\WINDOWS
Pause