How come i wrote a NO-BREAK SPACE in xterm+bash ?

["Thomas Schmitt" <scdbackup@gmx.net>]

Hi,

i just had some interesting minutes with this riddle in bash
on xterm:

  $ ls -l .. | wc
  ls: cannot access .. : No such file or directory

The refusal sticks to the command in libreadline's history
buffer and to copy+paste, but not to a manually retyped
command:

  $ ls -l .. | wc
     70     623    4159

Finally i found out that the refusing command line does not
have an ASCII Blank (decimal 32) before the pipe symbol
but rather UTF-8 code (194,160) which means U+00A0
"NO-BREAK SPACE".
Obviously this does not count as whitespace in bash (vanilla
Debian 8.1 install). The error message had (194,160) between
".." and ":".

Now i riddle how my chair, my US-ASCII keyboard, and the
problem inbetween managed to produce such a character
in the bash (libreadline) command line of an xterm.

Does anybody have an idea how to reproduce this ?
(In order to better avoid it.)


Have a nice day :)

Thomas