Qp0zGetTimeofDay()--Get Current Software Clock Time

Syntax

 #include <sys/time.h>

 int Qp0zGetTimeofDay (struct timeval *tp,
                       struct timezone *tzp);

  Service Program Name: QP0ZCPA

  Default Public Authority: *USE

  Threadsafe: Yes

The Qp0zGetTimeofDay() function retrieves the current software clock time and places it in the timeval structure pointed to by tp. If tzp is not NULL, the time zone information is returned in the timezone structure pointed to by tzp.

The software clock maintains a time that can be set independently of the system clock. It is not integrated with the system and will be removed in a future release. The gettimeofday() function should be used instead.

Parameters

tp: (Output) A pointer to a timeval structure that contains the time in seconds and microseconds since 1 January 1970, 00:00:00 UTC (epoch-1970).
tzp: (Output) A pointer to a timezone structure that contains the local time zone (measured in minutes west of Greenwich) and a flag that, if nonzero, indicates daylight saving time applies locally during the appropriate part of the year.

Authorities and Locks

None

Return Value

0	Qp0zGetTimeofDay() was successful.
-1	Qp0zGetTimeofDay() was not successful. The `errno` variable is set to indicate the error.

Error Conditions

If Qp0zGetTimeofDay() is not successful, errno usually indicates one of the following errors. Under some conditions, errno could indicate an error other than those listed here.

[EINVAL]

An invalid parameter was found.

A parameter passed to this function is not valid.

[EFAULT]

The address used for an argument is not correct.

In attempting to use an argument in a call, the system detected an address that is not valid.

While attempting to access a parameter passed to this function, the system detected an address that is not valid.

Error Messages

None.

Usage Notes

For the best performance, specify NULL for the tzp parameter.
If the value of the environment variable QIBM_USE_SFWCLK is "N", Qp0zGetTimeofDay() calls gettimeofday() to get the current UTC time from the system clock.

Related Information

The <sys/time.h> file (see Header Files for UNIX^®-Type Functions)
gettimeofday()--Get Current UTC Time
Qp0zAdjTime()--Adjust Software Clock
Qp0zSetTimeofDay()--Set Software Clock

Example

The following example gets the current software clock time.

Note: By using the code examples, you agree to the terms of the Code license and disclaimer information.

#include <sys/time.h>
#include <stdio.h>
#include <errno.h>

int main(int argc, char *argv[])
{
    struct timeval now;
    int rc;

    rc=Qp0zGetTimeofDay(&now, NULL);
    if(rc==0) {
        printf("Qp0zGetTimeofDay() successful.\n");
        printf("time = %u.%06u\n",
                now.tv_sec, now.tv_usec);
    }
    else {
        printf("Qp0zGetTimeofDay() failed, errno = %d\n",
                errno);
        return -1;
    }

    return 0;
}

Example Output:

Qp0zGetTimeofDay() successful.
time = 866208142.290944

API introduced: V5R3

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