25 Feb 2005 edp   » (Observer)

mount: only root can do that

Why can't a non-root user do this?

$ dd if=/dev/zero of=img bs=1024k count=1
$ mke2fs -F img
$ mkdir mnt
$ mount -t ext2 -o loop img mnt
$ 

That's (IIUC) the standard way to create an initial ram disk for the linux kernel (as documented in eg its Documentation/initrd.txt).

mkcramfs OTOH doesn't require root privileges; any user can run that program to produce a cramfs image from a directory of its contents.

(But the existence of that tool seems to be a result of the fact that cramfs as a filesystem is readonly, so the above method doesn't work -- you can't create any content in the empty filesystem, because it's readonly -- so they were forced to make a separate tool. I'm not aware of corresponding tools for other filesystems. It's too bad the general method above doesn't work for non-root users. It seems unfortunate that just "mounting" a file to see what's packaged up in it -- that's what a filesystem image is, it's basically just like a ".tar.gz" file isn't it? -- why should that be a security risk?)

two-column xterm (and emacs)

Sometimes "top" output is more lines than fit in an xterm on my screen. But I have width enough for another xterm next to it. I'd like a "two-column" xterm so that the second xterm is treated as a vertical extension of the first one.

I'd also like the same thing in Emacs, where I split the screen down the middle (C-x 3) but the right half is a second column extending the buffer on the left half.

Googling "two-column xterm" came up empty.

(Actually I'm running gnome-terminal, not xterm. But varying the search terms doesn't seem to help.)

I wonder about Emacs. Someone has probably implemented what I want for Emacs, right?! Hmm. Looking at "apropos column" results ... "2C-two-columns" sounded promising but I wasn't able to get it to do anything useful. Reading some more docs I see it's meant for editing files with two columns of text. But I just want to display (and scroll and edit) a regular "single column" text file (buffer, really) using *more* than one column, continuing the text from the bottom of one column at the top of the next column (and so on, with three or more columns.)

Hmm... If I had the two-column xterm (gnome-terminal, whatever) presumably I could *run* Emacs in it and it would Just Work and I'd have my two-column Emacs display. But window-splitting would be kinda weird... Hmm...

UPDATE: C-x 3 M-x follow-mode does exactly what I want! Found it by surfing emacswiki.org a bit... Oh and I see AlanShutko pointed out the same thing; thanks!

RIP HST

ABC news: Writing in The New York Times in 1973, Christopher Lehmann-Haupt worried Thompson might someday "lapse into good taste." "That would be a shame, for while he doesn't see America as Grandma Moses depicted it, or the way they painted it for us in civics class, he does in his own mad way betray a profound democratic concern for the polity," he wrote. "And in its own mad way, it's damned refreshing."

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