The character in question is U+005c, the REVERSE SOLIDUS, also known as the backslash or ”. It is the path separator for Windows, which is encoded at 0x5c across all of the ANSI code pages.
Since path separators are a pretty important requirement, the title of this post may seem a little scary — how could it not be a backslash, a reverse solidus?
Well, on Japanese code page 932, 0x5c is the YEN SIGN, and on Korean code page 949, 0x5c is the WON SIGN.
Which is not to say that 0x5c does not act as a path separator — it still does. And which is also not to say that the Unicode code points for the Yen and the Won (U+00a5 and U+20a9) do act as path separators — because they do not.
Of course the natual round trip mapping between U+005c and 0x5c happens on all code pages, and both U+00a5 and U+20a9 have one-way ‘best fit’ mappings to 0x5c on their respective code pages. This requirement technically went away with Unicode, when the characters were encoded separately.
However, the issue is not a simple one of there not being space in the old code page and lots of space in Unicode, where customers will instantly move away from the not backslash path separators.
In practice, after many years of code page based systems in Japan and Korea using their respective currency symbols as the path separators, it is believed customers were simply used to this appearance. And there was therefore little interest in changing that appearance (when the system settings were Japanese or Korean) to anything but those symbols.
To support this expectation, Japanese and Korean fonts, whenever the default system locale is set to Japanese or Korean, respectively, will display the currency symbol rather than the backslash when U+005c is shown.
But whether or not this is really what customers want is still an open question. Andrew Tuck of PSS here at Microsoft noted:
When one of my customer’s from Korea was visiting here, I asked him if it bothered him that the backslash doesn’t appear as a backslash. It did bother him, and he believes it bothers most of his countrymen. However, he was fatalistic about it, “What can we do to change it. It’s been this way for a long time. We are used to it.”
Hardly a glowing recommendation, is it?
And as Norman Diamond noted in his comments on this very blog (in this post), there are plenty of people in Japan who may not care for the convention, either.
Of course there is no ‘right’ answer here, and I would imagine that you would find plenty of people who would be unhappy with such a change, just as there are those who would be unhappy with the status quo. Which perhaps explains why the status quo seems to be as it is — those people who would like a change are resigned to the idea that it may never happen. And so they are now used to it….