[ Previous | Next | Contents | Home | Search ]
AIX Version 4.3 Kernel and Subsystems Technical Reference, Volume 1

pincf Kernel Service

Purpose

Manages the list of free character buffers.

Syntax

#include <sys/types.h>
#include <sys/errno.h>
#include <cblock.h>
int pincf (delta)
int delta;

Parameter

delta Specifies the amount by which to change the number of free-pinned character buffers.

Description

The pincf service is used to control the size of the list of free-pinned character buffers. A positive value for the delta parameter increases the size of this list, while a negative value decreases the size.

All device drivers that use character blocks need to use the pincf service. These drivers must indicate with a positive delta value the maximum number of character blocks they expect to be using concurrently. Device drivers typically call this service with a positive value when the ddopen routine is called. They should call the pincf service with a negative value of the same amount when they no longer need the pinned character blocks. This occurs typically when the ddclose routine is called.

Execution Environment

The pincf kernel service can be called in the process environment only.

Return Values

The pincf service returns a value representing the amount by which the service changed the number of free-pinned character buffers.

Implementation Specifics

The pincf kernel service is part of Base Operating System (BOS) Runtime.

Related Information

The waitcfree kernel service.

I/O Kernel Services in AIX Kernel Extensions and Device Support Programming Concepts.


[ Previous | Next | Contents | Home | Search ]