개요

• 솔라나라에 설명된 어플리케이션에 대해 맨 페이지를 찾아 출력한다.
• MAN 페이지에 대한 설명은 윈디하나의 솔라나라: MAN 페이지을 참고하자.
• svcadm(8)을 검색하려면 섹션에서 8 을 선택하고, 맨 페이지 이름에 svcadm을 입력하고 검색을 누른다.

drv_usectohz(9f)

drv_usectohz(9F)               Kernel Functions               drv_usectohz(9F)



NAME
       drv_usectohz - convert microseconds to clock ticks

SYNOPSIS
       #include <sys/types.h>
       #include <sys/ddi.h>

       clock_t drv_usectohz(clock_t microsecs);

INTERFACE LEVEL
       Architecture independent level 1 (DDI/DKI).

PARAMETERS
       microsecs    The number of microseconds to convert.


DESCRIPTION
       The  drv_usectohz()  function  converts  a  length of time expressed in
       microseconds to a number of system clock ticks. The time  arguments  to
       timeout(9F) and delay(9F) are expressed in clock ticks.


       The drv_usectohz() function is a portable interface for drivers to make
       calls to timeout(9F) and delay(9F) and remain binary compatible  should
       the driver object file be used on a system with a different clock speed
       (a different number of ticks in a second).

RETURN VALUES
       The value returned is the number of system clock  ticks  equivalent  to
       the  microsecs  argument. No error value is returned. If the clock tick
       equivalent to microsecs is too large to be represented  as  a  clock_t,
       then the maximum clock_t value will be returned.

CONTEXT
       The drv_usectohz() function can be called from user, interrupt, or ker‐
       nel context.

SEE ALSO
       delay(9F), drv_hztousec(9F), timeout(9F)


       Writing Device Drivers in Oracle Solaris 11.4

NOTES
       If  the   microsecs   argument   to   drv_usectohz()   is   less   than
       drv_hztousec(9F),  drv_usectohz()  returns one tick. This, coupled with
       multiplication, can  result  in  significantly  longer  durations  than
       expected.  For example, on a machine where hz is 100, calling drv_usec‐
       tohz() with a microsecs value less than 10000 returns a result  equiva‐
       lent to 10000 (1 tick). This type of mistake causes code such as"5000 *
       drv_usectohz(1000)" to compute a duration of 50 seconds instead of  the
       intended 5 seconds.



Oracle Solaris 11.4               24 Apr 2008                 drv_usectohz(9F)