Error in malloc

[prathiksa]

i started learning c,i know malloc is for dynamic allocation but i dont know how to use with structure,using the image1 parameters i have to allocate space in memory
//it showing error "incompatible types when assigning ------

typedef struct
{
height;
width;
depth;
}VALUES;
VALUES image1,image2;

image2 = (char*)malloc (image1.height,image1.width,image1.depth(sizeof(char));//how to write this code (image 2 is of type structure)

[ledow]

You have to give malloc a single number - the total size of everything you want to malloc in bytes.

So:

image2 = malloc(image1.height * image1.width * image1.depth * sizeof(char))

Assuming the height, width and depth are all stored in bytes. More likely you want to divide them by 8 because they are more likely to correspond to the number of BITS and there are 8 bits in a byte.

P.S. I removed your cast of the return value of malloc because people hate that. FAQ's are available telling you why.
P.P.S. sizeof(char) is by definition 1.

[prathiksa]

thanks,but it still says
incompatible types when assigning to type VALUES from type void*

[Salem]

Try this

// a collection of whatever it is you want to store
typedef struct
{
    int height;
    int width;
    int depth;
}VALUES;

VALUES *image1; // a pointer to some VALUES

image1 = malloc( howManyValuesYouWantToStore * sizeof(*image1) );

[std10093]

Don't cast what malloc returns

[prathiksa]

it says height in something not a structure or unoin

[prathiksa]

thanks,i fix it
no error

[prathiksa]

oooh again it showing errors
i need to assign the image1 size to image2
but it says
height in something not a structure or union
width in something not a structure or union
-------------

[AndiPersti]

It would really help us if you show us the relevant code.

Bye, Andreas