Terminal command returns unwanted response.

Just as the title says, I'm following a step-by-step guide to Terminal commands for making a bootable Chromium OS USB drive and getting a dead end. After entering (where X = my disk identifier) and successfully unmounting the disk, it has me uncompress the .img file and doesn't say I need to put it somewhere specific. It continues to have me execute (again X = identifier) while making sure the "ChromeOS.img" matches the file name I have and it returns "dd: ChromeOS.img: No such file or directory.". Can someone help me here? I'll admit I don't know enough about Terminal commands to understand if I'm putting the wrong file path or w/e and I'm just copying the directions. If someone can let me know, you'll get a "Thank you". Thanks, haha.

- ImageX

The if switch here signifies the input file. The way you have it set now assumes that "ChromeOS.img" is in the current working directory. As the error informs you, dd can't find the image in the directory that you're currently working in. Your best bet (and the easiest solution): put the full path to the ChromeOS image as the value for the if switch. So, for example, if ChromeOS.img was in ~/Desktop, change the command to:
Out of curiosity, what disk is /dev/rdiskX? I've never seen an "rdisk" device file in OS X before.

Thanks for the response. It seems to be working now. To be honest, I don't even know what rdisk means. Like I said, I'm just following step-by-step guide on how to make a bootable Chrome OS USB drive. The drive in this case is my 4GB Flash drive. Thanks again.

You need to double check the of switch value then. The of switch value is the output disk. Are you sure that /dev/rdiskX (X meaning a disk number) is the flash drive? Did you check this at some point while going through the steps?

Yes, I checked my Flash Drive's identifier in disk utility before doing this. It was disk1.

disk1 or rdisk1? Sorry if I seem pedantic here but this difference can be the source of drastic consequences (plus, like I said, I've never seen an rdisk device file before).

It was "disk1" and even in his guide he was assuming the ID would be diskX not rdiskX so I'm not sure why, but the guide said to use rdiskX in that code and when I hit enter my USB drive's activity light was flashing and it completed successfully. And I don't have a problem with you asking these questions lol. I'd like to know why it said to use it as rdisk also. Seems to have worked though. Going to try and boot it on my Windows PC now.

It appears that rdisk is simply a raw device file. This allows you to bypass the filesystem's cache & buffer which makes writes quicker. I assume though that this increases the risk of problems that are offset by making use of the filesystem's caching features. I'll have to defer to a *nix nerd here though.

Let us know if the Flash Drive Chrome OS works. I did that ages ago when the beta of Chrome OS came out. Same commands with DD but no rdisk!

Yeah, as I understand it (I'm stretching my knowledge here), you don't need the "r" in front. Doing so only ensure that you interact with the drive as a raw device.

And yes, please do let us know how it works out. Are you building it from source? Last time I tried, it didn't go well.