Need more efficient way to append character arrays

[XfoxX]

Hey my character array stores a list of items but my implementaion is very inefficient. Here is what I do:

1. I Create a buffer of 100 chars.
2. My function search for the items in a text file.
3. If the list goes over 100 chars then i create new char * and move all the list to the new one.

3. If the list goes over 100 chars then i create new char * and move all the list to the new one.

step 3 is my problem because I'm creating a new buffer for the whole list everytime when the list needs more space.

Is it possible to append the new buffer to the old list, instead of creating a new buffer for the whole list?

Thanx in advance

PS: I can't use linked list because I need to pass the items back to client app.

[jim mcnamara]

 #define SIZE 100
 char *buf;
 int counter=1;
 buf = (char*) malloc(SIZE);
..................
// we need more space
 buf = realloc(buf,++counter * SIZE); // add 100 bytes

The new buffer has all the old stuff at the start, plus free space at the end

[XfoxX]

realloc will work with new and delete?

thanx again

[CornedBee]

You shouldn't assume that it does, but it will at least with the MSVC CRT implementation.

[XfoxX]

Two more question, why every c++ book tells you to use new instead of malloc?
Malloc is suitable if the buffer goes over 2000 character?

Thanks

[CornedBee]

a) Because you don't need to cast the pointer returned from malloc.
b) new knows the size of a type
int *p = new int[100];
is better than
int *p = (int*)malloc(100 * sizeof(int));
c) ONLY new calls object constructors!

[jim mcnamara]

Saying it another way:

new is less prone to errors in typing, and is standard for C++.
You have to use it to create new instances of a class.

For C, malloc or calloc are standard.

You can use realloc for now with MSVC++. Just watch porting it to another compiler.