NAME
ctod —
macros related to bytes, pages,
and disk blocks
SYNOPSIS
#include <sys/param.h>
size
ctod(
size
x);
size
dtoc(
size
x);
size
ctob(
size
x);
size
btoc(
size
x);
size
dbtob(
size
x);
size
btodb(
size
x);
DESCRIPTION
The
ctod family of macros can be used to convert between
bytes, pages (“clicks”), and disk blocks.
The following table lists the possible conversions:
Macro |
From |
To |
ctod() |
pages |
disk blocks |
dtoc() |
disk blocks |
pages |
ctob() |
pages |
bytes |
btoc() |
bytes |
pages |
dbtob() |
disk blocks |
bytes |
btodb() |
bytes |
disk blocks |
These are typical macros that may appear with different names in other operating
systems. Examples include
btop() and
btopr() in Solaris.
SEE ALSO
param(3)
HISTORY
Some of these macros appeared in
Version 7 AT&T
UNIX.
CAVEATS
The described macros make no assumptions about the type of the input parameter.
A caller should ensure that neither integer overflow nor integer underflow are
possible.