Editing String (computer science) (section)

==== Null-terminated ====
{{Main|Null-terminated string}}

The length of a string can be stored implicitly by using a special terminating character; often this is the [[null character]] (NUL), which has all bits zero, a convention used and perpetuated by the popular [[C (programming language)|C programming language]].<ref>
{{Citation
 |last1        = Bryant
 |first1       = Randal E.
 |author-link = Randal Bryant
 |last2       = David
 |first2      = O'Hallaron
 |title       = Computer Systems: A Programmer's Perspective
 |place       = Upper Saddle River, NJ
 |publisher   = Pearson Education
 |year        = 2003
 |edition     = 2003
 |url         = http://csapp.cs.cmu.edu/
 |isbn        = 0-13-034074-X
 |page        = 40
 |url-status     = live
 |archive-url  = https://web.archive.org/web/20070806075942/http://csapp.cs.cmu.edu/
 |archive-date = 2007-08-06
}}
</ref> Hence, this representation is commonly referred to as a '''C string'''. This representation of an ''n''-character string takes ''n'' + 1 space (1 for the terminator), and is thus an [[implicit data structure]].

In terminated strings, the terminating code is not an allowable character in any string. Strings with ''length'' field do not have this limitation and can also store arbitrary [[binary data]].

An example of a ''null-terminated string'' stored in a 10-byte [[Buffer (computer science)|buffer]], along with its [[ASCII]] (or more modern [[UTF-8]]) representation as 8-bit [[hexadecimal number]]s is:

{| class="wikitable" style="margin-left: auto; margin-right:auto"
 |-
 | <code>F</code>  || <code>R</code>  || <code>A</code>  || <code>N</code>  || <code>K</code>
 | <small>[[Null character|NUL]]</small>
 | style="background: #DDD" | <code style="background: #DDD">k</code>
 | style="background: #DDD" | <code style="background: #DDD">e</code>
 | style="background: #DDD" | <code style="background: #DDD">f</code>
 | style="background: #DDD" | <code style="background: #DDD">w</code>
 |-
 | 46<sub>[[Hexadecimal#Using 0–9 and A–F|16]]</sub> || 52<sub>16</sub> || 41<sub>16</sub> || 4E<sub>16</sub> || 4B<sub>16</sub>
 | 00<sub>16</sub>
 | style="background: #DDD" | 6B<sub>16</sub>
 | style="background: #DDD" | 65<sub>16</sub>
 | style="background: #DDD" | 66<sub>16</sub>
 | style="background: #DDD" | 77<sub>16</sub>
 |}

The length of the string in the above example, "<code>FRANK</code>", is 5 characters, but it occupies 6 bytes. Characters after the terminator do not form part of the representation; they may be either part of other data or just garbage. (Strings of this form are sometimes called ''ASCIZ strings'', after the original [[assembly language]] directive used to declare them.)