SVR5

# drv_usectohz(D3)

**drv_usectohz --
convert microseconds to clock ticks
**

## Synopsis

#include <sys/types.h>
#include <sys/ddi.h>
clock_t drv_usectohz(clock_t *microsecs*);

## Description

**drv_usectohz** converts the length of time expressed by
*microsecs*, which is in units of microseconds,
into units of clock ticks.
### Arguments

*microsecs*-
The number of microseconds to convert to equivalent clock ticks.

### Return values

The value returned is the smallest number of clock ticks that represent
a time interval equal to or greater than the *microsecs* argument.
No error value is returned.
If the number of ticks equivalent
to the *microsecs* argument is too large to be represented as a
**clock_t**,
then the maximum **clock_t** value will be returned.
## Usage

Several functions either take time values expressed in clock ticks as
arguments
[**timeout**(D3),
**timeout**(D3),
**delay**(D3)]
or return time values expressed in clock ticks
[**drv_getparm**(D3)].
The length of a clock tick can vary across different implementations,
and therefore drivers should not include any hard-coded assumptions
about the length of a tick.
**drv_usectohz** and the complementary function
**drv_hztousec**(D3)
can be used, as necessary, to convert between
microseconds and clock ticks.
### Context and synchronization

All
contexts.
### Hardware applicability

All
### Version applicability

ddi:
1, 2, 3, 4, 5, 5mp, 6, 6mp, 7, 7mp, 7.1, 7.1mp, 8, 8mp
## References

**delay**(D3),
**drv_getparm**(D3),
**drv_hztousec**(D3),
**itimeout**(D3)
**timeout**(D3)
``Delays and busy-waits'' in *HDK Technical Reference*

*
19 June 2005
*

© 2005 The SCO Group, Inc. All rights reserved.

OpenServer 6 and UnixWare (SVR5) HDK - June 2005