Node:Internationalization, Next:Changing Structure, Up:Shortcomings
diff, diff3 and sdiff treat each line of
input as a string of unibyte characters. This can mishandle multibyte
characters in some cases. For example, when asked to ignore spaces,
diff does not properly ignore a multibyte space character.
Also, diff currently assumes that each byte is one column
wide, and this assumption is incorrect in some locales, e.g., locales
that use UTF-8 encoding. This causes problems with the -y or
--side-by-side option of diff.
These problems need to be fixed without unduly affecting the performance of the utilities in unibyte environments.
The IBM GNU/Linux Technology Center Internationalization Team has
proposed some patches to support internationalized diff
http://oss.software.ibm.com/developer/opensource/linux/patches/i18n/diffutils-2.7.2-i18n-0.1.patch.gz.
Unfortunately, these patches are incomplete and are to an older
version of diff, so more work needs to be done in this area.