The function gettimeofday() can get the time as well as a timezone.
Read more in the Linux Reference.
Questions tagged [gettimeofday]
100 questions
2
votes
1 answer
OSX gettimeofday syscall on x86_64 seems to not work
I'm making a call to gettimeofday via the syscall instruction using 64bit code.
I can't get any results back and am getting told via Dtrace that the call worked with no errors, but the registers I get back from the call are garbage.
I do the…
Chris Hinsley
- 71
- 4
2
votes
2 answers
C++ gettimeofday() returns the same value
/*
* Returns time in s.usec
*/
float mtime()
{
struct timeval stime;
gettimeofday(&stime,0x0);
return (float)stime.tv_sec+((float)stime.tv_usec)/1000000000;
}
main(){
while(true){
cout<
Stefan Rogin
- 1,499
- 3
- 25
- 41
2
votes
2 answers
usleep() to calculate elapsed time behaves weird
I am calculating time elapsed in milli seconds for each successive call to handler function using the code below. When i use usleep(1000) i.e. 1 ms time difference between each call is 10 ms and when i use usleep(1000000) i.e. 1 sec surprisingly…
vikas_2kx
- 37
- 6
2
votes
1 answer
Week Incrementation using Javascript
I'm working on a reminders application using Phonegap [Javascript + Html5] in which the user enters the weekly task he wants to be reminded of and I'm supposed to alert a notification every week on that day.
Now the point is: I use Phonegap Local…
Sana Joseph
- 1,948
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2
votes
1 answer
C++: fmodf() & fmod() - Strange Results?
So, I needed a way to be able to get the second of the day, so I messed around with fmod() & gettimeofday() (Mac OSX). However, I came into some odd results along the way:
#include
#include
#include
class A…
Richard J. Ross III
- 55,009
- 24
- 135
- 201
1
vote
1 answer
C: gettimeofday() produces the same value every run
I'm trying to print the time in ISO-8601 with decisecond precision.
YYYY-MM-DDThh:mm:ss.s
Here is my code:
#include
#include
#include
#include
#include
void milli_time(char* dest, struct…
julianc
- 177
- 1
- 10
1
vote
1 answer
why struct timeval return 0 after first use? and how to over come this problem?
I am making a simple Sender and Reciever to check the time difference between using Reno CC algorithm and a Cubic CC algorithm.
in order to make an accurate comparison between them I am using struct timeval instead of clock, and I am also adding a…
Dolev Dublon
- 643
- 1
- 6
- 16
1
vote
1 answer
Why the 2nd diff is so different from the others, using gettimeofday in a loop?
This function is quite new for me, so I just writed a little program to get familiar with it.
Here's a my program (just printing laps between several calls of gettimeofday).
#include
#include
#include
#include…
UnDesSix
- 68
- 1
- 1
- 8
1
vote
0 answers
Which value will gettimeofday () return when the system's RTC has not yet been set to the current time?
It's about an all-fresh system without NTP or any other external time signal source, whose real-time clock hasn't even been set yet manually. When I query it by using
int gettimeofday (struct timeval *tv, struct timezone *tz);
…which return value…
Neppomuk
- 1,102
- 1
- 11
- 24
1
vote
1 answer
Gettimeofday not working when assigned to variable
I have a simple timestamp issue. I am trying to get a timestamp using gettimeofday and it all works as it should when I print the value to the terminal however when I assign it to a variable it does not. I can not figure out what im doing wrong. The…
JakobVinkas
- 1,003
- 7
- 23
1
vote
1 answer
Why does a timerfd periodic Linux timer expire a little before than expected?
I am using a Linux periodic timer, in particular, timerfd, which I set to expire periodically, for instance, every 200 ms.
I noticed, however, that the timer seems to expire, sometimes, a little before with respect to the timeout I set.
In…
es483
- 361
- 2
- 16
1
vote
1 answer
Accurate Timestamps using gettimeofday and localtime
I'm attempting to monitor system time elapsed across multiple applications and data paths via gettimeoday and localtime. In this example, I want to grab the system time (microsecond percision) right before my code runs. I'm currently doing it like…
fbd39j
- 35
- 2
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1
vote
1 answer
date uses gettimeofday?
When I do: date system call on freeBSD, does it internally use gettimeofday ?
Another que: how do I know where the code of "date" command sitting on the system?
Thanks.
hari
- 9,439
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1
vote
0 answers
Undefined behavior using gettimeofday
#include
#include
static long elapsedTime(struct timeval &then)
{
struct timeval when;
gettimeofday(&when, NULL);
long result = (when.tv_sec - then.tv_sec) * 1000;
result += (when.tv_usec - then.tv_usec) /…
heyblackduck
- 117
- 13
1
vote
3 answers
logical time versus physical time in ubuntu linux
i am measuring physical time between two events like this:
#include
#include
timeval wall_time0;
timeval wall_time1;
// start of period measurement
gettimeofday( &wall_time0 , 0);
...stuff happening
// end of period…
lurscher
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