![]() ![]() The ability to represent a null character does not always mean the resulting string will be correctly interpreted, as many programs will consider the null to be the end of the string. A null character can be placed in a URL with the percent code . Other escape sequences that are found in use in various languages are \000, \x00, \z, or \u0000. In many languages ( such as C, which introduced this notation), this is not a separate escape sequence, but an octal escape sequence with a single octal digit 0 as a consequence, \0 must not be followed by any of the digits 0 through 7 otherwise it is interpreted as the start of a longer octal escape sequence. The null character is often represented as the escape sequence \0 in source code, string literals or character constants. This allows the string to be any length with only the overhead of one byte the alternative of storing a count requires either a string length limit of 255 or an overhead of more than one byte (there are other advantages/disadvantages described in the null-terminated string article). Today the character has much more significance in the programming language C and its derivatives and in many data formats, where it serves as a reserved character used to signify the end of a string, often called a null-terminated string. On punched tape, the character is represented with no holes at all, so a new unpunched tape is initially filled with null characters, and often text could be inserted at a reserved space of null characters by punching the new characters into the tape over the nulls. When electromechanical teleprinters were used as computer output devices, one or more null characters were sent at the end of each printed line to allow time for the mechanism to return to the first printing position on the next line. The original meaning of this character was like NOP-when sent to a printer or a terminal, it has no effect (some terminals, however, incorrectly display it as space). In 8-bit codes, it is known as a null byte. It is often abbreviated as NUL (or NULL, though in some contexts that term is used for the null pointer). It is available in nearly all mainstream programming languages. It is present in many character sets, including those defined by the Baudot and ITA2 codes, ISO/IEC 646 (or ASCII), the C0 control code, the Universal Coded Character Set (or Unicode), and EBCDIC. If you need that, you'll have to define your own EDataType (that wraps ), and does encoding and decoding.The null character (also null terminator) is a control character with the value zero. But no version of XML can serialize the null character 0x0. ![]() XML 1.0 cannot serialize many of these, but XML 1.1 can, so you could use .(String) with the value 1.1 to serialize these. And finally, there are the control characters, <= 0x1F. You should use OPTION_SKIP_ESCAPE_URI mapped to FALSE if your URIs for cross references contain characters that need escaping but best you avoid that by not using resources with things like, or
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