forcing char array to act as int array

[chuck]

Hello,
I am trying to 'force' a character array to act as an int array. I
want to use 4 chars to store an actual int , in the array, not a number
converted to a string. So every 4 characters of my array is really a
full integer value.

Can anyone post a simple example on how to do this?

Thanks,
chuck

[Ondra Holub]

Re: forcing char array to act as int array

On 14 Ún, 13:45, chuck <noem...@gmail. comwrote:

Hello,
I am trying to 'force' a character array to act as an int array. I
want to use 4 chars to store an actual int , in the array, not a number
converted to a string. So every 4 characters of my array is really a
full integer value.
>
Can anyone post a simple example on how to do this?
>
Thanks,
chuck

You need int type, where sizeof() is 4. Then:

char* buffer = "abcdefghijklmn opqrstuvwx";
int32_t* ibuffer = reinterpret_cas t<int32_t*>(buf fer);

[Daniel T.]

Re: forcing char array to act as int array

On Feb 14, 7:45 am, chuck <noem...@gmail. comwrote:

  I am trying to 'force' a character array to act as an int array.  I
want to use 4 chars to store an actual int , in the array, not a number
converted to a string.  So every 4 characters of my array is really a
full integer value.
>
Can anyone post a simple example on how to do this?

Are the ints in your system sizeof( 4 )? Is the memory in the char
array formatted with the same endian as what the system uses?

If so, then simply int* myArr = reinterpret_cas t<int*>( myChar );
Otherwise, you will have to do some real work converting the raw
memory into the format you need.

[Default User]

Re: forcing char array to act as int array

Daniel T. wrote:

Are the ints in your system sizeof( 4 )?

They'd have to be, wouldn't they?




Brian

[peter koch]

Re: forcing char array to act as int array

On 14 Feb., 13:45, chuck <noem...@gmail. comwrote:

Hello,
  I am trying to 'force' a character array to act as an int array.  I
want to use 4 chars to store an actual int , in the array, not a number
converted to a string.  So every 4 characters of my array is really a
full integer value.
>
Can anyone post a simple example on how to do this?
>
Thanks,
chuck

Do it the other way around: regard your integer variable as an array
of four (if that is the size of your int) characters and std::copy to/
from the ints.

/Peter

[James Kanze]

Re: forcing char array to act as int array

On Feb 14, 7:48 pm, "Daniel T." <danie...@earth link.netwrote:

On Feb 14, 7:45 am, chuck <noem...@gmail. comwrote:

I am trying to 'force' a character array to act as an int array. I
want to use 4 chars to store an actual int , in the array, not a number
converted to a string. So every 4 characters of my array is really a
full integer value.

Can anyone post a simple example on how to do this?

Are the ints in your system sizeof( 4 )? Is the memory in the
char array formatted with the same endian as what the system
uses?

If so, then simply int* myArr = reinterpret_cas t<int*>( myChar );

That's a good recepe for a core dump on a lot of machines.
You're forgetting alignment considerations.

Otherwise, you will have to do some real work converting the
raw memory into the format you need.

No real work, just a bit of shifting and masking.

--
James Kanze (GABI Software) email:james.kan ze@gmail.com
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