Thread: Doubt with struct and malloc

Good afternoon everyone,

I need a struct where its internal fields are dynamically allocated and the number of records is also dynamically allocated.

My question is that I have no idea how it is possible to implement this!

Imagine the struct below, each field will have a different size and will vary according to the input text.

Example: Field1 can receive 1000 bytes or 3000 bytes

The number of records in the struct will start at 0, and will increase as a record is registered.

Code:

struct {
    char
      Field1[   20],
      Field2[   20],
      Field3[ 1001],
      Field4[ 1001],
      Field5[ 1001],
      Field6[30000];
} Fields[50000];

I know how to use malloc to increase each field.

Code:

Field1 = malloc(101);

But how do I increase the number of records in the struct?

I also don't know if I can have for example different sizes in each record, since in a simple struct of char field[100] this is true for all records.

Record 1 = Field1 = 100 bytes
Record 2 = Field1 = 600 bytes

Can anyone help?