Getting hold of the current directory in a batch file.
A common UNIX shell idiom is to write things like cwd=`pwd` to save the current directory so that in case be used later when other things might have changed it. For a long time I didn't think this was possible in Windows batch files. It turns out that it is, but it isn't pretty and it does generalise to getting the output of any command.
Edit: Thanks to the anonymous people who pointed out that the standard shell environment variable %CD% provides this functionality already. I've left the rest of the article in place because it's still a useful idiom for getting the output of any command into an environment variable.
People have gone to great lengths to get this functionality on Windows but such techniques don't have the convenience of a simple variable assignment.
It turns out that it can be done using a side effect of the hoopy new for statement. This functionality may be XP specific - I haven't checked on anything older. I very much doubt it will work on anything older than Windows 2000.
Here's the code to get hold of the current directory:
for /f %%i "delims=" in ('cd') do set cwd=%%i
Try for /? to get the full information but here's a brief description. The /f flag invokes this hoopy new mode, "delims=" indicates that we don't want to treat spaces and tabs as delimiters and ('cd') specifies that we should run the cd command to get the current directory.