exception : 0xC0000005: Access Violation

Hi,

I am getting the following exception

First-chance exception in TestMansoor.exe: 0xC0000005: Access Violation

When i run the following code

1 int main(void)
2 {
3 char* str1 = "MA";
4 char s = str1[0];
5 str1[0] = 'r';
6 return 0;
7 }

i'm getting exception on line 5. Why?

Bye.

re: exception : 0xC0000005: Access Violation

batista wrote:[color=blue]
> Hi,
>
> I am getting the following exception
>
> First-chance exception in TestMansoor.exe: 0xC0000005: Access Violation
>
> When i run the following code
>
> 1 int main(void)
> 2 {
> 3 char* str1 = "MA";
> 4 char s = str1[0];
> 5 str1[0] = 'r';
> 6 return 0;
> 7 }
>
> i'm getting exception on line 5. Why?
>[/color]

str is a constant string , you can only access it. If you want to
change the contents of str, you will either have to declare it as an
array of allocate memory for it.

re: exception : 0xC0000005: Access Violation

batista wrote:[color=blue]
> Hi,
>
> I am getting the following exception
>
> First-chance exception in TestMansoor.exe: 0xC0000005: Access Violation
>
> When i run the following code
>
> 1 int main(void)
> 2 {
> 3 char* str1 = "MA";
> 4 char s = str1[0];
> 5 str1[0] = 'r';
> 6 return 0;
> 7 }
>
> i'm getting exception on line 5. Why?
>
> Bye.
>[/color]

becouse "MA" is a string iteral, and as such cant be modified, even
though its possilble to get a non const pointer to it for some bizzare
reason

your code is more less equivalent of

((char*)"MA")[0] = 'r';

if you want to get a copy of "MA" what you want to do is
char str1[] = "MA";
now str1[0] is modifiable

re: exception : 0xC0000005: Access Violation

batista wrote:[color=blue]
> Hi,
>
> I am getting the following exception
>
> First-chance exception in TestMansoor.exe: 0xC0000005: Access Violation
>
> When i run the following code
>
> 1 int main(void)
> 2 {
> 3 char* str1 = "MA";
> 4 char s = str1[0];
> 5 str1[0] = 'r';
> 6 return 0;
> 7 }
>
> i'm getting exception on line 5. Why?[/color]


Line 3 should read:

const char* str1 = "MA";

It is specifically allowed by the standard as your original because of
the volume of legacy code that would otherwise break. (IMHO a bad move
by the standards comittee.)

You can however rewrite line 3 like:

char str1[] = "MA";

.... now you're free to change the three characters that is str1.

re: exception : 0xC0000005: Access Violation

In article <1131356517.625797.72670@g49g2000cwa.googlegroups. com>,
batista <saadtheleon@gmail.com> wrote:[color=blue]
>Hi,
>
>I am getting the following exception
>
>First-chance exception in TestMansoor.exe: 0xC0000005: Access Violation
>
>When i run the following code
>
>1 int main(void)
>2 {
>3 char* str1 = "MA";
>4 char s = str1[0];
>5 str1[0] = 'r';
>6 return 0;
>7 }
>
>i'm getting exception on line 5. Why?[/color]

Check out http://www.comeaucomputing.com/techtalk/#stringliteral
--
Greg Comeau / Celebrating 20 years of Comeauity!
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