Modifying a Clock Time

diff -r 43e37759235e -r 51a74ef9ed63 Symbian3/SDK/Source/GUID-29AE56A8-DA08-5FB3-89F1-26B4308336BC.dita --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/Symbian3/SDK/Source/GUID-29AE56A8-DA08-5FB3-89F1-26B4308336BC.dita Wed Mar 31 11:11:55 2010 +0100 @@ -0,0 +1,52 @@ + + + + + +Modifying a Clock Time

Use the clock_settime() function to modify the clock time.

Important: The clock time can be modified only by a process having the WriteDeviceData capability.

The following example code demonstrates how the current clock time can be moved forward by a minute.

The following example code performs the following tasks:

Gets the clock id of the system clock and stores it in ClockId.
Gets the current time associated with ClockId using clock_gettime() and stores it in CurrTime.
Increments current time by a minute.
Sets the current time as CurrTime using clock_settime().

#include <time.h> +#include <stdio.h> +#include<errno.h> +#include<string.h> +int main() + { + int Ret; + clockid_t ClockId; //Stores the clock id of the system clock + struct timespec CurrTime; //Stores the current time + memset(&CurrTime, 0, sizeof (struct timespec)); + + //Will return the supported clock id only for the pid_t of 0. + Ret = clock_getcpuclockid(0,&ClockId); + if (Ret == 0) + { + //get the current time of ClockId. + if(clock_gettime(ClockId, &CurrTime) == 0) + { + CurrTime.tv_sec+=60; //forward the time by one minute + //set the new time for ClockId. + Ret = clock_settime(ClockId, &CurrTime); + if (Ret != 0) + { + printf("clock_settime () failed with %d\n", errno); + } + else + { + printf("clock_settime() passed\n"); + } + } + else + { + printf("clock_gettime() failed with %d\n", errno); + } + } + else + { + printf("clock_getcpuclockid () failed with %d\n", errno); + } + return Ret; + }

The output of the above program is:

clock_settime() passed \ No newline at end of file