Expert: Narendra - 4/18/2006

Question
Hi,

I have a another question. I know that by using malloc and relloc you can assign memory to a variable pointer but you have to know the size before hand. What if you don't?

I'm trying to write a simple function that accepts a string from the user and store it in a location. But the string can be anywhere from 0 - infinty.
How do you allocate dynamic memory at runtime? or how do you find out the length of the inputted string without storing it first (is that possible?)?

Thanks

Answer
Make a initial guess (or calculate) and allocate using malloc().
In the loop when the string is growing infinitely, you will know by how much amount it will grow each time.
So, add that to the current size and use realloc() to extend the allocation.
By using this strategy, you can go on increasing the size till your memory is exhausted:-)