- NetBSD Manual Pages
MSTOHZ(9) NetBSD Kernel Developer's Manual MSTOHZ(9)
Powered by man-cgi (2021-06-01).
Maintained for NetBSD
by Kimmo Suominen.
Based on man-cgi by Panagiotis Christias.
mstohz, hztoms -- convert between milliseconds and system clock ticks
The mstohz() macro can be used to convert time in milliseconds to system
clock ticks, as used by the callout(9) facility, in an integer-overflow
safe way. Conversely, hztoms() converts system clock ticks to millisec-
These macros are defined in the <sys/param.h> header. Individual ports
can have a processor-specific, more efficient version implemented in
their <machine/param.h> header as a define.
The return value is either the number of clock ticks or milliseconds for
the specified value.
param(3), callout(9), tvtohz(9)
Neither mstohz() nor hztoms() make use of expensive 64-bit integer arith-
metic. The result from mstohz() will be rounded down to one second if
the parameter is larger than 131072 milliseconds.
NetBSD 9.3 October 20, 2011 NetBSD 9.3