How to tell if my YEN symbol is a backslash or a YEN?

I have a little program which is used to print the backslash symbol to the PDF file. In most English OS a backslash is displayed as a backsl开发者_运维知识库ash, and my program works just fine. However, in Japanese OS or Korean OS my program starts to have problem. In those OS, a backslash is displayed as a YEN or WON symbol, but my program exports them as a backslash. I know that this is a bug of the font which has been around but i still want to find a solution for it. Does anyone know how to tell if my backslash is displayed like a backslash or something else?

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You would not know what character is display by font. They are in same character code 0x5C

Instead don't use system default font (for eg, ＭＳ Ｐゴシック), assign english font for eg, Arial

Or

Use Unicode backslash ∖