Non-breaking space is easy to write accidentally and impossible or hard to distinguish from regular space.

Is there possibility that hard disk is working unreliably? Is there a way to check the drive? It has ext3 filesystem.

I can confirm this!

Clean install of Hardy 64bit.

tero2@tero-desktop:~$ lspci | grep VGA
bash:  grep: command not found
tero2@tero-desktop:~$

tero2@tero-desktop:~$ ls -l / | grep home
bash:  grep: command not found

tero2@tero-desktop:~$ ls -l / | /bin/grep home
bash:  /bin/grep: No such file or directory

tero2@tero-desktop:~$ echo "mooo" | cowsay
bash:  cowsay: command not found

I am using the i386 version.

Are you sure you aren't inserting an altgr+space character after the pipe character instead of just the normal space? I'm suspecting this because there is an additional empty space after "bash: (somecommand): command not found"

If grep wasn't found, bash would say:
bash: grep: command not found
you are seeing:
bash: grep: command not found

Looks like Flyspray ate the double space from my previous comment. Anyway, you are seeing double empty space after the first colon in the bash error message, which you shouldn't.

crwl, you are right about the altgr+space character. But it didn't matter in ubuntu 7.10 terminals xterm and xfce4-terminal tested. Why is the change? I guess I'll have to quit using any space there.

under system -> preferences -> keyboard -> layouts -> layout options you can choose what shift+space should do. marking this as invalid.

The bug is not about shift+space, but altgr+space. You can not configure it in Xubuntu's desktop environment. Can anybody tell why is the effect of altgr+space changed in (X)ubuntu 8.04?

i am sorry about invalidating your bug! feel free to reopen the bug and file it against the relevant packages. this greatly increases the chance of being noticed by the right guys.

Problem seems to be in keyboard layout. ie. AltGr + space produces different byte sequence in us- and fi-layouts. This can be verified with following commands. (In both cases the space between quotes is typed by pressing AltGr+space)

$ setxkbmap us
$ echo " " | hexdump
0000000 0a20
0000002

$ setxkbmap fi
$ echo " " | hexdump
0000000 a0c2 000a
0000003

I did a little more searching and found out, that altgr+space behaviour can be altered with xkb option nbsp. Adding following line to the keyboard InputDevice section in xorg.conf avoids this issue by disabling the nbsp.

Option "XkbOptions" "nbsp:none"

In KDE systems this can be done alternatively by going to System Settigns -> Regional & Language -> Keyboard layout -> Xkb Options, and selecting option "Space key outputs usual space at any level." for "Using space key to input non-breakable space character".

Thanks Juhamatti Niemelä for the hack. I think it would be user-friendly that identically looking commands work same way by default, too.

Hi jarnos,

Please attach the output of `lspci -vvnn`, and attach your /var/log/Xorg.0.log file from after reproducing this issue. If you've made any customizations to your /etc/X11/xorg.conf please attach that as well.

i think the above was a bulk reply and does not apply here, because those settings do not matter here at all. it is more a design question in x (or perhaps rather in your virtual terminal application or your shell or whereever) if it is good to have chars that look exactly the same but behave completely different. like 1 and I and l or O and 0, but just for whitespace (tab vs nl vs space vs nbsp ...)

Michael Nagel, 1, I and l look different in terminal, also 0 and O.

i know. this bug is about whitescreen. the other chars were just a example to make clear what you mean (it is your bug, isnt it?). because Bryce' request does not make much sense in this case.

This feature can be configured in:
System
  ->Preferences
  ->Keyboard
  ->Layouts
  ->Layout options...
  ->Using space key to input non-breakable...

Few issues:

 * Changing the configuration option from "Default" to "Space key outputs usual space at any level" does not have any effect on my computer. AltGr+Space in gnome-terminal still outputs nbsp.
 * What does "Default" mean?

For some reason Juhamatti Niemelä's XkbOptions do not work either.

Hi jarnos,

Please attach the output of `lspci -vvnn`, and attach your /var/log/Xorg.0.log file from after reproducing this issue. If you've made any customizations to your /etc/X11/xorg.conf please attach that as well.

Hi bryceharrington,

I don't understand why you are asking all the attachments, but I hope you tell. Please note that I could patch the problem by customizing xrog.conf as presented at https://bugs.launchpad.net/ubuntu/+source/xorg/+bug/218637/comments/11. However, the customazion is commented out in the attachment to reproduce the issue.

I hope the attachments are worth the trouble.

I tested under Xubuntu 8.10. Problem continues to exist; furthermore the xorg.conf setting featured by Juhamatti Niemelä does not work there, I suppose, since "InputDevice" sections are ignored there AFAIK.

I suppose the GUI way to configure does work in Gnome, but I can't find such option in Xfce4's keyboard preferences.

tp, "Space key outputs usual space at any level" works here in ubuntu 8.10 (Gnome session).

The change was made to conform standards. The Finns of you can read the details here:

http://kotoistus.tksoft.com/linux/space.html

if the app doesn't show the difference, then it's a bug in the app, not X.

Timo Aaltonen, can you tell me which terminal does not have such a bug then? Or should shells interpret non-breaking space as normal space?

I don't know. Maybe needs wider discussion than possible on this bug.

Just to point out, that correct solution to disabling NBSP is
[ytti@sci ~]% cat /etc/hal/fdi/policy/remove_nbsp.fdi
<?xml version="1.0" encoding="UTF-8"?>
<deviceinfo version="0.2">
  <device>
    <match key="info.capabilities" contains="input.keys">
      <merge key="input.x11_options.XkbOptions" type="string">nbsp:none</merge>
    </match>
  </device>
</deviceinfo>
[ytti@sci ~]%

Instead of mocking with xorg.conf. This requires restart of hal and xorg. If you do not wish to restart
immediately but still wish to disable nbsp you should issue 'sudo setxkbmap -option "nbsp:none'.

Thanks, Saku Ytti. The command is 'sudo setxkbmap -option "nbsp:none"' to be strict.

At least in ubuntu 14.04 (with Xfce) you don't need to be superuser to run
setxkbmap -option "nbsp:none"
I run this as an autostarted application to avoid trouble.

And as for the first workaround in #28, my system does not even have /etc/hal/

As for apps mentioned in #25, the list is big. Libreoffice shows the difference, but I don't know other programs.

Is there any font that would display non-breaking space differently?

I make the mistake regularly of writing a non-breaking space instead of a regular space, when writing shell scripts. It produces errors that are very difficult to detect.

geany has setting in Edit > Preferences > Editor > Display > Show white space.
I think it should be default. It shows one pixel mark for regular white space, which is hard to see, though. It shows just space for non breaking space. Inverting colors helps a bit.

you'd need to file this upstream