Chapter 1

Figure 8.1
CBufFlat, which puts all the bytes in a single heap cell. This means that access to any byte
is quick (it just adds the byte index to the beginning of the buffer). However, memory
allocation can be inefficient, so that it might not be possible to expand the buffer when
desired, even though there may be more than enough bytes of unused heap available.
CBufSeg, which puts the bytes in multiple heap cells, each of which is a segment of the
buffer. For large buffers that are constantly changing in size, and where insertions and
deletions part-way through the buffer are frequent, segmented buffers are much more
efficient than flat buffers. Finding a particular byte theoretically requires a walk of the entire
segment structure: CBufSeg caches a reference to the last-used byte, which speeds up
most operations.
The buffers example illustrates the functions available. The mainL()function is as
follows:
void mainL()
{
CBufBase* buf=CBufSeg::NewL(4);
CleanupStack::PushL(buf);
//
_LIT8(KTxt1,"hello!");
buf->InsertL(0,KTxt1);
printBuffer(buf);