A few years ago I changed over from a Dell PC Keyboard to an Apple keyboard.

I had to delete some files in a temp folder and typed the command as I was always used to, and pressed enter.

Immediately realised something was wrong and then saw the "*" replaced with a "/". Did not have a fun afternoon.

http://i.imgur.com/4k4SOpF.jpg

My worst has been accidentally removing zip - back in my Slackware days IIRC. I was trying to upgrade and so I removed the old one and then went to install the new one and couldn't install it again as the packager used zip and all the downloads I could find were tar.gz (or tar.bz2 or whatever).

That was the first, and last time I think, that I used cpio. Phew.

But the superuser privileges should have overridden such directory permissions, even 25 years ago....

Yes, but if you can't run the chmod binary...

No, root can still run chmod, because its superuser privileges override the new restrictive directory perms. That was my point.

Maybe the original problem was actually "chmod a-rwx /bin/chmod" ... That would mean even the superuser couldn't execute /bin/chmod anymore, so you'd have to do something more creative to reset the executable bit on /bin/chmod. Like compile a C program that calls the chmod system call, or:

  mv /bin/chmod /bin/chmod.orig
  cp -p /bin/ls /bin/chmod
  cp /bin/chmod.orig /bin/chmod

> Like compile a C program that calls the chmod system call

The compiler wouldn't be executable anymore either

Yes, it would. Like he said, you can still run it unless you specifically removed its permissions.

The explanation for what made him type that is what interests me. It would be like accidentally cutting your left hand clean off with a steak knife while you were eating dinner.

My bash is set to use vim bindings (set -o vi) and I constantly loop through commands. I am guilty of doing this while sleepy and sometimes I think I have cd to another directory when in fact I have not. I rm-ed (too) many things that way.

I gave the vi mode a very short try, but it doesn't seem to make as much sense in a shell. If it has you accidentally deleting things, you might want to ask how much is it really worth. In vim you can undo.

One can use the shared library loader to invoke binaries that do not have executable bit set, comes in handy once in a while.

  $ cp /bin/chmod .
  $ chmod -x ./chmod
  $ /lib/ld-2.19.so ./chmod
  ./chmod: missing operand
  Try './chmod --help' for more information.

My worst has been accidentally removing zip - back in my Slackware days IIRC. I was trying to upgrade and so I removed the old one and then went to install the new one and couldn't install it again as the packager used zip and all the downloads I could find were tar.gz (or tar.bz2 or whatever).

That was the first, and last time I think, that I used cpio.

Oh, the pain! I remember doing that 25 years ago too, ouch.