NAME

btop - convert size in bytes to size in pages (round down)

SYNOPSIS

#include <sys/ddi.h>

unsigned long btop(unsigned long numbytes);

INTERFACE LEVEL

Architecture independent level 1 (DDI/DKI).

ARGUMENTS

numbytes

Number of bytes.

DESCRIPTION

btop( ) returns the number of memory pages that are contained in the specified number of bytes, with downward rounding in the case that the byte count is not a page multiple. For example, if the page size is 2048 ,then btop(4096) returns 2 ,and btop(4097) returns 2 as well. btop(0) returns 0 .

RETURN VALUES

The return value is always the number of pages. There are no invalid input values, and therefore no error return values.

CONTEXT

btop( ) can be called from user or interrupt context.

SEE ALSO

btopr (9F),ddi_btop(9F), ptob(9F)

Writing Device Drivers