strcpy和strcat的返回类型 [英] strcpy and strcat's return type
问题描述
为什么strcpy和strcat（以及某些非标准的
实现中的strupr和strlwr）返回一个char *？当然这些逻辑（和DMA安全）
）返回类型将无效？
谢谢，
James McLaughlin。
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哈希：SHA1
ze ********** ****@yahoo.com 写道：
为什么strcpy和strcat（以及某些非标准
实现中的strupr和strlwr） ）返回一个char *？当然这些逻辑（和DMA安全）
返回类型是无效的？
为什么strcat（）返回一个void *，当它的两个参数都是
char *，并且函数被定义为处理字符串？
strcpy（）也是如此：为什么你认为它应该返回无效
*而不是char *？
ISTM，因为两个函数
a）取char *作为参数（而不是void *），
b）处理char *数据，并且
c）创建char *指针最好描述的结果，
两个函数/应该/返回char *指向它们已生成的结果的指针。
- -
Lew Pitcher，IT专家，企业数据系统
企业技术解决方案，道明银行金融集团
（此处表达的意见是我自己的，不是我的意见雇主的）
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Lew Pitcher：泽************** @ yahoo.com ：
....为什么strcpy和strcat（以及某些非标准
实现中的strupr和strlwr）返回char *？当然这些逻辑（和DMA安全）
返回类型是无效的吗？
为什么strcat（）返回void *，当它们都是'的论点是
char *，函数被定义为处理字符串？
他说无效，不是无效*。并回答实际问题：我认为，
他们返回char *以允许这样的东西
返回strcat（strcpy（buf，path），file ）;
Jirka
Jirka Klaue写道：
Lew Pitcher：< blockquote class =post_quotes> ze ************** @ yahoo.com ：
...为什么strcpy和strcat（以及某些非标准的strpr和strlwr
implementation）返回一个char *？当然这些逻辑（和DMA安全）
返回类型是无效的吗？
为什么strcat（）返回void *，当它们都是'的论点是
char *，函数被定义为处理字符串？
他说无效，不是无效*。并回答实际问题：我认为，
他们返回char *以允许返回strcat（strcpy（buf，path），file）;
此外，原本没有虚函数这样的东西吗？ （我
知道我在没有无效的平台上工作。）
-
+ ----- -------------------- + -------------------- + -------- --------------------- +
| Kenneth J. Brody | www.hvcomputer.com | |
| kenbrody / at\spamcop.net | www.fptech.com | #include< std_disclaimer.h> |
+ ------------------------- + -------------- ------ + ----------------------------- +
不要给我发电子邮件：< mailto：Th ************* @ gmail.com>
Hi,
Why do strcpy and strcat (and strupr and strlwr in some nonstandard
implementations) return a char*? Surely the logical (and DMA-safe)
)return type for these would have been void??
Thanks,
James McLaughlin.
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ze**************@yahoo.com wrote:Hi,
Why do strcpy and strcat (and strupr and strlwr in some nonstandard
implementations) return a char*? Surely the logical (and DMA-safe)
)return type for these would have been void??
Why should strcat() return a void *, when both of it''s arguments are
char *, and the function is defined as working on character strings?
The same goes for strcpy(): why do you think that it should return void
* rather than char *?
ISTM that, since both functions
a) take char * as arguments (and not void *),
b) work on char * data, and
c) create results best described by char * pointers,
both functions /should/ return char * pointers to the results that they
have generated.
- --
Lew Pitcher, IT Specialist, Enterprise Data Systems
Enterprise Technology Solutions, TD Bank Financial Group
(Opinions expressed here are my own, not my employer''s)
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BGAvh0N9wubb8W9NJLmfxIA=
=6TrQ
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Lew Pitcher:ze**************@yahoo.com:
....Why do strcpy and strcat (and strupr and strlwr in some nonstandard
implementations) return a char*? Surely the logical (and DMA-safe)
)return type for these would have been void??
Why should strcat() return a void *, when both of it''s arguments are
char *, and the function is defined as working on character strings?
He said void, not void *. And to answer the actual question: I think,
they return char * to allow such things as
return strcat(strcpy(buf, path), file);
Jirka
Jirka Klaue wrote:
Lew Pitcher:ze**************@yahoo.com:
...Why do strcpy and strcat (and strupr and strlwr in some nonstandard
implementations) return a char*? Surely the logical (and DMA-safe)
)return type for these would have been void??
Why should strcat() return a void *, when both of it''s arguments are
char *, and the function is defined as working on character strings?
He said void, not void *. And to answer the actual question: I think,
they return char * to allow such things as
return strcat(strcpy(buf, path), file);
Besides, wasn''t there originally no such thing as a void function? (I
know I worked on platforms without "void".)
--
+-------------------------+--------------------+-----------------------------+
| Kenneth J. Brody | www.hvcomputer.com | |
| kenbrody/at\spamcop.net | www.fptech.com | #include <std_disclaimer.h> |
+-------------------------+--------------------+-----------------------------+
Don''t e-mail me at: <mailto:Th*************@gmail.com>
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