Editing String (computer science) (section)

== Character string functions ==
{{See also|Comparison of programming languages (string functions)}}

[[String function]]s are used to create strings or change the contents of a mutable string. They also are used to query information about a string. The set of functions and their names varies depending on the [[programming language|computer programming language]].

The most basic example of a string function is the [[string length]] function – the function that returns the length of a string (not counting any terminator characters or any of the string's internal structural information) and does not modify the string. This function is often named <code>[[comparison of programming languages (string functions)#length |length]]</code> or <code>len</code>. For example, <code>length("hello world")</code> would return 11. Another common function is [[concatenation]], where a new string is created by appending two strings, often this is the + addition operator.

Some [[microprocessor]]'s [[instruction set architecture]]s contain direct support for string operations, such as block copy (e.g. In [[intel x86]]m <code>REPNZ MOVSB</code>).<ref>{{cite web|url=https://docs.oracle.com/cd/E19120-01/open.solaris/817-5477/eoizn/index.html|title=x86 string instructions|url-status=live|archive-url=https://web.archive.org/web/20150327220944/http://docs.oracle.com/cd/E19120-01/open.solaris/817-5477/eoizn/index.html|archive-date=2015-03-27}}</ref>