struct question：NULL终止char *数组 [英] struct question: NULL terminated char* array
问题描述
char * testCharArray [] = {
" one"，
" two"，
" three"，
四，
五，
六，
NULL，
};
上面的代码初始化一个NULL终止的char *数组。问题
是为什么括号后需要一个分号（即。};），以及为什么
应该在NULL之后有逗号？ （我在书中看到开始linux
编程第3版。在auther之后附加一个逗号，删除
逗号对代码没有任何作用）
$我使用的b $ b编译器是gcc 3.4.4
char *testCharArray[] = {
"one",
"two",
"three",
"four",
"five",
"six",
NULL,
};
The above code initializes a NULL terminated char* array. The question
is why is a semi-colon needed after the bracket (ie. };), and why
should there be a comma after NULL ? (I saw in the book beginning linux
programming 3rd ed. the auther appended a comma after NULL, removing
the comma does nothing to the code)
compiler I used was gcc 3.4.4
推荐答案
chy101 ... @ gmail.com写道：
chy101...@gmail.com wrote:
char * testCharArray [] = {
" one"，
" two"，
三，
四，
五，
六，
NULL，
};
上面的代码初始化一个NULL终止的char *数组。问题
是为什么在括号后需要一个分号（即。};）
char *testCharArray[] = {
"one",
"two",
"three",
"four",
"five",
"six",
NULL,
};
The above code initializes a NULL terminated char* array. The question
is why is a semi-colon needed after the bracket (ie. };)
因为C中的声明以a结尾分号，结束括号
表示初始化列表的结尾，而不是
声明的结尾。
Because declarations in C end with a semicolon, the closing bracket
signifies the end of the initializer list, not the end of the
declaration.
和为什么在NULL之后会有逗号？ （我在书中看到开始
linux编程第3版。在auther之后附加一个逗号，
删除逗号对代码没有任何作用）
and why should there be a comma after NULL ? (I saw in the book beginning
linux programming 3rd ed. the auther appended a comma after NULL,
removing the comma does nothing to the code)
初始化列表末尾的尾随逗号是一个功能
旨在帮助自动代码生成器，它们不是必需的。
Robert Gamble
Trailing commas at the end of an initializer list are a feature
intended to aid automatic code generators, they are not required.
Robert Gamble
Robert Gamble写道：
Robert Gamble wrote:
chy101 ... @ gmail.com写道：
chy101...@gmail.com wrote:
> char * testCharArray [] = {
" one"，
" two"，
three，
four，
five，
six，
NULL，
};
>char *testCharArray[] = {
"one",
"two",
"three",
"four",
"five",
"six",
NULL,
};
.... snip ...
.... snip ...
>
>
>为什么在NULL之后会有逗号？ （我在书中看到
开始linux编程第3版。在auther之后附加一个逗号
，删除逗号后对代码不做任何操作）
>and why should there be a comma after NULL ? (I saw in the book
beginning linux programming 3rd ed. the auther appended a comma
after NULL, removing the comma does nothing to the code)
初始化列表末尾的尾随逗号是一个功能
，旨在帮助自动代码生成器，它们不是必需的。
Trailing commas at the end of an initializer list are a feature
intended to aid automatic code generators, they are not required.
IMO更好的方式来编写该声明（并且与所有C版本的b / b兼容）是：
char * testCharArray [] = {" one"
，" two"
，""
，四
，五
，六
，NULL
} ;
-
一些信息链接：
news：news.announce.newusers
http://www.geocities.com/nnqweb/
http://www.catb.org/~esr/faqs/smart-questions .html
http://www.caliburn.nl/ topposting.html
http：//www.netmeister .ORG /新闻/ learn2quote .html
IMO a better way to write that declaration (and be compatible with
all C versions) is:
char *testCharArray[] = { "one"
, "two"
, "three"
, "four"
, "five"
, "six"
, NULL
};
--
Some informative links:
news:news.announce.newusers
http://www.geocities.com/nnqweb/
http://www.catb.org/~esr/faqs/smart-questions.html
http://www.caliburn.nl/topposting.html
http://www.netmeister.org/news/learn2quote.html
Robert Gamble写道：
Robert Gamble wrote:
chy101 ... @ gmail.com写道：
chy101...@gmail.com wrote:
char * testCharArray [] = {
" one"，
" two"，
三，
四，
" five"
" six" ;，
NULL，
};
char *testCharArray[] = {
"one",
"two",
"three",
"four",
"five",
"six",
NULL,
};
以及为什么在NULL之后会有逗号？
and why should there be a comma after NULL ?
初始化列表末尾的尾随逗号是一个功能
旨在帮助自动代码生成器，它们不是必需的。
Trailing commas at the end of an initializer list are a feature
intended to aid automatic code generators, they are not required.
为了更清楚，这个尾随的逗号意味着该程序是
而不是一个结构良好的C90程序 - 虽然这是一个非常普遍的
编译器扩展允许它。
To be clearer, this trailing comma means the program is
not a well-formed C90 program -- although it is a very common
compiler extension to allow it.
这篇关于struct question：NULL终止char *数组的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
