Are Unicode and Ascii characters the same?

Unicode is a way to assign unique numbers (called code points) to characters from nearly all languages in active use today, plus many other characters such as mathematical symbols. There are many ways to encode Unicode strings as bytes, such as UTF-8 and UTF-16. ASCII assigns values only to 128 characters (a-z, A-Z, 0-9, space, … Read more

How does UTF-8 encoding identify single byte and double byte characters?

For example, “Aݔ” is stored as “410754” That’s not how UTF-8 works. Characters U+0000 through U+007F (aka ASCII) are stored as single bytes. They are the only characters whose codepoints numerically match their UTF-8 presentation. For example, U+0041 becomes 0x41 which is 01000001 in binary. All other characters are represented with multiple bytes. U+0080 through … Read more

Unicode Support in Various Programming Languages

Perl Perl has built-in Unicode support, mostly. Sort of. From perldoc: perlunitut – Tutorial on using Unicode in Perl. Largely teaches in absolute terms about what you should and should not do as far as Unicode. Covers basics. perlunifaq – Frequently asked questions about Unicode in Perl. perluniintro – Introduction to Unicode in Perl. Less … Read more

Newline symbol unicode character

There are several possibilities. The choice may depend on font, too, since not all of them are available in all fonts, and some of them have rather varying shapes, and some work better in small sizes than others: ⤶ U+2936 ARROW POINTING DOWNWARDS THEN CURVING LEFTWARDS ↵ U+21B5 DOWNWARDS ARROW WITH CORNER LEFTWARDS ⏎ U+23CE … Read more

Isn’t on big endian machines UTF-8’s byte order different than on little endian machines? So why then doesn’t UTF-8 require a BOM?

The byte order is different on big endian vs little endian machines for words/integers larger than a byte. e.g. on a big-endian machine a short integer of 2 bytes stores the 8 most significant bits in the first byte, the 8 least significant bits in the second byte. On a little-endian machine the 8 most … Read more

How does a Unicode character get mapped to a glyph in a font?

TrueType fonts consist of a number of sections, most importantly for this question a table of “glyphs” and a table (“cmap”) for mapping characters to those glyphs. Long story short, the operating system uses the “cmap” table to convert characters into glyph indexes, substituting a default glyph for any which have no matching entry. Unfortunately … Read more

Hata!: SQLSTATE[HY000] [1045] Access denied for user 'divattrend_liink'@'localhost' (using password: YES)