I would like to get the current timestamp of realtime clock in my BASH script. The hwclock command can print out the current time, but it is not timestamp.
I have considered parsing hwclock's output and then convert the results to a timestamp, but it seems the hwclock output will vary if the current locale gets changed. So if I give my script to my clients, they could use different locales than mine, and my parsing results could be wrong (and of course the timestamp will be wrong).
So my question is, what would be the best way to get timestamp from RTC? Thanks in advance.
When you call hwclock -D, you get an output like the following which contains the timestamp:
hwclock from util-linux 2.27.1
Using the /dev interface to the clock.
Assuming hardware clock is kept in UTC time.
Waiting for clock tick...
...got clock tick
Time read from Hardware Clock: 2018/09/27 09:03:46
Hw clock time : 2018/09/27 09:03:46 = 1538039026 seconds since 1969
Time since last adjustment is 1538039026 seconds
Calculated Hardware Clock drift is 0.000000 seconds
Thu 27 Sep 2018 11:03:45 CEST .749554 seconds
The following command parses this output to extract the actual timestamp:
sudo hwclock -D | grep "Hw clock time" | sed "s/.* = \([0-9]\+\) seconds .*/\1/"
Related
When viewing submitted jobs managed by Slurm, I would like to have the time limit column (specified by %l) to show only hours, instead of the usual days-hours:minutes:seconds format. This is the command I am currently using:
squeue --format="%.6i %.5P %.25j %.8u %.8T %.10M %.5l %.15b %.5C %.6D %R" --sort=+i --me
and this is the example output:
276350 qgpu jobname username RUNNING 1:14:14 1-00:00:00 gres:gpu:v100:1 18 1 s31n02
So, in this case, I would like the elapsed time to remain as is (1:14:14), but the time limit to change from 1-00:00:00 to 24. Is there a way to do it?
This is the way Slurm displays the dates. Elapsed time will eventually be displayed the same way (days-hours:minutes:seconds) after 23:59:59.
You can use a wrapper script to convert into a different format. Or if you know the time limit is no more than a day, just set the time limit to 23:59:00 by using --time=1439.
salloc -N1 --time=1439 bash
Using your squeue command:
166 mypartition interactive jyvet RUNNING 7:36 23:59:00 N/A 1 1 mynode
I have two timestamps in formats :
Timestamp 1 (Variable - RunStartDate): Thu May 3 14:12:54 CDT 2018
Timestamp 2 (Variable - RunEndDate): Thu May 3 18:11:46 CDT 2018
I want the difference of number of hours between these two timestamps in UNIX shell. (I.e. RunEndDate - RunStartDate in hours)
Please help, I am new to UNIX and it is throwing me errors when I just try to subtract the two.
You have a few options here, such as calling out to Perl or Python and using a date/time library to do the math for you. Another option is to use the date program to convert the dates to seconds, subtract the values, and then convert back to hours. Unfortunately, you can't do floating-point math in Bash, so we'll have to call out to a helper program to do that, too.
START=$(date -d "$RunStartDate" +"%s")
END=$(date -d "$RunEndDate" +"%s")
HOURS=$(bc -l <<< "($END - $START) / 3600")
Note that this will only work on GNU systems (e.g. Linux).
I have a time-stamp like 7:00:00, which means 7am.
I would like to write a short command that returns 06:45:00, or simply 06:45, preferably using date command so that I can avoid long shell script. Do you have any elegant solution?
I'm also looking for a 24h format. For example, 12:00:00 - 15 minutes = 11:45:00.
With GNU date, use 7:00:00 AM - 15 minutes as d (--date) string :
% date -d '7:00:00 AM - 15 minutes' '+%H:%M'
06:45
+%H:%M sets the output format as HH:MM.
On BSD variants Date has a -v flag which can be used to take the current timestamp and display the result of a positive or negative adjustment.
This will subtract 15mins from the current timestamp:
date -v -15M
We have a little issue with a time calculation in Bash.
Lets give you a little explaination about the situation up here.
We download every 5 minutes one file from an FTP server. This file contains time information about the data in this file. But the timeformat of the file is in UTC, and our local time is UTC+2. The files contains information about the past 5 minutes from local time. Now we have the following code:
TIMESTAMP=$(echo "$(TZ=UTC date "+%Y%m%d%H%M") - ($(date +%M)%5)-5" | bc)
That works well for several hours but after 55 minutes it becomes a problem. So we dont able to get the files with the 55 minutes, 60 minutes.
So if local time is: 19:47
The file with time 17:40 (utc) is available on the server at 19:45 local time
The time the files are available on the server are not constant too bad...
19:00, 19:05, 19:10 etc... but sometimes the file is one minute later....
This is my crontab file:
SHELL=/bin/sh
PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/home/kbroeren/cronscripts
*/1 * * * * /home/kbroeren/cronscripts/radar >> /home/kbroeren/radar_log.txt 2>&1
*/5 * * * * sudo /usr/bin/python /home/kbroeren/cronscripts/radar_plot.py >>/home/kbroeren/out.txt 2>&1
Is there a better and correct way to do this ?
You seem to be looking for %s:
date +%s
This returns:
%s seconds since 1970-01-01 00:00:00 UTC
You'd need to change the arithmetic a bit, though.
The date command can convert to and from a number of date and time formats. If you want to do arithmetic with dates and times, it's probably easiest to convert to “seconds since the unix epoch”, do the arithmetic, and convert back to the time format of your choice.
You might consider something like:
date --date="#$(echo $(TZ=UTC date +%s) - $(date +%s)'%(5*60)-(5*60)' | bc)"
I am trying to shift the dates of a series of files by 9 hours. I've reached as far as this:
for i in *.MOV; do touch -r "$i" -d "-9 hours" "$i"; done
This should work in recent systems, but the touch command in OSX seems to be a bit outdated and not to support the -d switch.
I'm using Snow Leopard. Any idea on the best option for doing this with a single line command? I don't want to create a script for this.
Ok, sorted it out. OSX comes with a gtouch command, that knows the -d switch. It's part of GNU coreutils. See the comments below for information regarding availability on specific MacOS versions.
For more information on using relative dates with the -d switch see the manual.
Looking at the Wikipedia Page for Touch, it appears you're accustomed to the GNU version of Touch. Which MacOS isn't using.
For what you want to do, look into the "SetFile" command, which gets installed with XCode tools. You have -d and -m options, which reset the Created and Modified dates & times respectively.
http://developer.apple.com/library/mac/#documentation/Darwin/Reference/ManPages/man1/SetFile.1.html
Donno OS X, but it should be easy enough to
get curr time stamp on the file
convert it to seconds
subtract 9 hours (9*60*60 secs) from it
convert it back to the format accepted by touch's -t option
run touch command
All this of course can be done in a single for loop on command line.
Here are simple examples from WikiPedia showing back and forth conversion.
# To convert a specific time stamp to Unix epoch time (seconds since 1970-01-01):
date +"%s" -d "Fri Apr 24 13:14:39 CDT 2009"
# 1240596879
# To convert Unix epoch time (seconds since 1970-01-01) to a human readable format:
date -d "UTC 1970-01-01 1240596879 secs"
# Fri Apr 24 13:14:39 CDT 2009
# Or:
date -ud #1000000000
# Sun Sep 9 01:46:40 UTC 2001
# or: Haven't tested this but should work..
date -d #1000000000 +%y%m%d%%H%M%S
# 010909014640