# WBT_CalcPacketbitmapSize

## C Specification

  #include <nitro/wbt.h> int WBT_CalcPacketbitmapSize(int block_size);

## Arguments

block_size | The size of the data to be received.

## Return Values

Returns the receive archive record bitmap buffer size required to receive the corresponding amount of data.

## Description

This calculates and acquires the receive archive record bitmap buffer size that is required when receiving a specified size of data with the `WBT_GetBlock` function. This function can only be used: In the case of a parent, after the `WBT_InitParent` function; In the case of a child, after the `WBT_RequestSync` function. If the transmission packet size and the receive block data size are already known, the `WBT_PACKET_BITMAP_SIZE` macro obtains the same results.

## See Also

`WBT_GetBlock`, WBT_PACKET_BITMAP_SIZE

## Revision History

02/18/2005 Changed description of packet bitmap to "receive archive record bitmap buffer"
09/21/2004 Initial version