sudo reboot

vi

One of the common questions about the Bourne and Korn shells is why only the second command will redirect both stdout and stderr (13.1) to a file:

$ cat food 2>&1 >file
cat: can't open food
$ cat food >file 2>&1
$

Although lots of sh manual pages don’t mention this, the shell reads arguments from left to right.

1. On the first command line, the shell sees 2>&1 first. That means “make the standard error (file descriptor 2) go to the same place as the standard output (fd1) is going.” There’s no effect because both fd2 and fd1 are already going to the terminal. Then>file redirects fd1 (stdout) to file. But fd2 (stderr) is still going to the terminal.
2. On the second command line, the shell sees >file first and redirects stdout to file. Next 2>&1 sends fd2 (stderr) to the same place fd1 is going - that’s to the file. And that’s what you want.

sample-bashrc

‘g’ stands for global, not sure what other parameters you can place there.

cat filename | tr -d [:space:]

This removes the whitespace and displays the results as standard out, you can then add a little bit to the command to save it to a file, like so:

cat filename | tr -d [:space:] >> fileoutname.txt

Props for sharing all of the great information, the only problem I have… is now I want to build one.

Perhaps on a miniature scale, 67 terabytes seems a bit excessive.

I’m still not 100% when/where/why I would use this. But it’s a pretty fantastic concept, portable Linux.

In an age of virtualization, we can now combine OS’s, and open an OS inside another OS. I wonder what fantastic/creative ways people will find to use this.