Platform: Windows (tested specifically on Windows 2003 R2)

Ye old command line FTP still comes in handy sometimes. For example, I'm using VMWare Server 2.x on a 2k3R2 box (64 bit in this case), and I run a few Linux guests. Today I was going to grab the latest CentOS release, 5.4 from one of the mirrors. IE won't download such a large file, so I found a mirror I could reach via ftp.

I fired up my cmd.exe, changed into my drive letter where I keep my source CD and DVD images, and started up the ftp. About a third of the way through downloading the 4+ GB iso, my machine started telling me it was running out of space on the C: drive. Huh?

Well it turns out the command line ftp program Microsoft ships with the OS saves anything it downloads to the local temporary directory. It doesn't just stream the download down to the current drive like a Linux based ftp would do. And after tinkering I discovered it respects the local environment variable TMP (and not the one named TEMP), apparently echoing back some roots in BSD or something.

So, the solution was to open a command window, type SET TMP=V:\tmp where the V: drive and tmp folders exist, and try my ftp again. Alteratively some other commerical ftp app might not do this but why spend money when you get the basics you need for free? You just need to watch what you're doing.