Search results
Results From The WOW.Com Content Network
Generally, an escape character is not a particular case of (device) control characters, nor vice versa.If we define control characters as non-graphic, or as having a special meaning for an output device (e.g. printer or text terminal) then any escape character for this device is a control one.
Magic quotes also use the generic functionality provided by PHP's addslashes() function, which is not Unicode-aware and is still subject to SQL injection vulnerabilities in some multi-byte character encodings. Database-specific functions such as mysql_real_escape_string() or, where possible, prepared queries with bound parameters, are preferred ...
Every regular expression can be written solely in terms of the Kleene star and set unions over finite words. This is a surprisingly difficult problem. As simple as the regular expressions are, there is no method to systematically rewrite them to some normal form. The lack of axiom in the past led to the star height problem.
In HTML and XML, a numeric character reference refers to a character by its Universal Character Set/Unicode code point, and uses the format: &#xhhhh;. or &#nnnn; where the x must be lowercase in XML documents, hhhh is the code point in hexadecimal form, and nnnn is the code point in decimal form.
A Unicode character is assigned a unique Name (na). [1] The name is composed of uppercase letters A–Z, digits 0–9, hyphen-minus and space.Some sequences are excluded: names beginning with a space or hyphen, names ending with a space or hyphen, repeated spaces or hyphens, and space after hyphen are not allowed.
On the opposite, the code point U+0085 is a valid control character in Unicode and ISO/IEC 10646, as well as in XML 1.0 and XML 1.1 documents (in all contexts), and its usage is not discouraged (it is treated as whitespace in many XML contexts, or as a line-break control similar to U+000D and U+000A in preformatted texts in some XML applications).
SQL statements also include the semicolon (";") statement terminator. Though not required on every platform, it is defined as a standard part of the SQL grammar. Insignificant whitespace is generally ignored in SQL statements and queries, making it easier to format SQL code for readability.
Historically, under PDP-6 monitor, [2] RT-11, VMS, and TOPS-10, [3] and in early PC CP/M 1 and 2 operating systems (and derivatives like MP/M) it was necessary to explicitly mark the end of a file (EOF) because the native filesystem could not record the exact file size by itself; files were allocated in extents (records) of a fixed size, typically leaving some allocated but unused space at the ...