NAME
param —
common parameters
SYNOPSIS
#include
<sys/param.h>
size
MAX(size
a, size b);
size
MIN(size
a, size b);
DESCRIPTION
The<sys/param.h> header
includes some common definitions and macros specific to
NetBSD. The header is perhaps best characterized as a
kernel equivalent of
<sys/types.h>. The following
list summarizes the provided definitions and macros.
- First and foremost, the header defines the version of
NetBSD. This is defined as
#define __NetBSD_Version__ 599004800 /* 5.99.48 */
The general format is “MMmmrrpp00”, where ‘MM’ and ‘mm’ denote the major and minor version, respectively, ‘rr’ is provided for compatibility, and ‘pp’ defines the patch level.
- Common utility macros such as
MAX() andMIN() as well as more specific macros such as STACK(9), ctod(9), mstohz(9), roundup(9), and setbit(9). - Numerous miscellaneous definitions such as limits, constants for the kernel memoryallocators(9), scale factors used by the scheduler, kthread(9) priorities, and many others.
- Definitions provided for historical and compatibility reasons. Examples range from definitions such as “#define BSD” to old priority levels used in the kernel.
SEE ALSO
HISTORY
A <param.h> header
appeared already in the Version 4 AT&T
UNIX.