Checks for an available buffer.
int testb(size, pri) register size; uint pri;
The testb utility checks for the availability of a message buffer of the size specified in the size parameter without actually retrieving the buffer. A successful return value from the testb utility does not guarantee that a subsequent call to the allocb utility will succeed; for example, when an interrupt routine takes the buffers.
If the buffer is available, the testb utility returns a value of 1. Otherwise, it returns a value of 0.
This utility is part of STREAMS Kernel Extensions.
The allocb utility.
List of Streams Programming References and Understanding STREAMS Flow Control in AIX Version 4.3 Communications Programming Concepts.