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uses the -u switch for UTC
Another way could be
echo $(($(date -ud "00:29:36" +%s)%86400))
Another function to stick into your .bashrc
This spits out the time two minutes in the future, but already formatted for pasting into your crontab file for testing without any thought required on your part. Frequently things don't work the way you expect inside a crontab job, and you probably want to find out now that your $PATH is completely different inside of cron or other global variables aren't defined. So this will generate a date you can use for testing now, and then later you can change it to run at 5:37 am on a Sunday evening.
Shorter, easier to remember version of cmd#7636
NTP is better, but there are situations where it can't be used. In those cases, you can do this to sync the local time to a server.
Requires you to have password free login to remote host ;)
Requires xclip and notify-send (If you want to put into clipboard and be notified when action is completed).
DATE=$(date +%Y-%m-%d_%H-%M-%S)-$(($(date +%N)/10000000));
HOST="ssh host of your choice";
DEST="destination folder without trailing slash";
URL="URL for file if uploaded to web enabled dir ie.
import -window root png:- | ssh $HOST "cat > $DEST/screenshot_$DATE.png";
echo $URL | xclip; notify-send -u low "Screenshot Taken" "Entire screen.\nCopied to clipboard"
No command substitution but subshell redirection
This version uses read instead of eval.
It's quite easy to capture the output of a command and assign it in a shell's variable:
day=$(date +%d)
month=$(date +%m)
But, what if we want to perform the same task with just one program invocation? Here comes the power of eval! date(1) outputs a string like "day=29; month=07; year=11" (notice the semicolons I added on purpose at date's custom output) which is a legal shell line. This like is then parsed and executed by the shell once again with the help of eval. Just setting 3 variables!
Inspired by LinuxJournal's column "Dave Taylor's Work the Shell".
I liked vaporub's suggestion, here a little simplification of the sed command.
Line can be modified as needed. This considers weekdays to be Mon-Fri. If run any working day it'll provide a parameters for the next working day for "at".
"beep" provided as a sample command.
This can be modified easily to include wait time. If you need something to run "D" days after today:
# D=4;if [ $(date +%u --date="${D} days") -lt 5 ];then AT="+${D} days";else AT="next monday";fi; echo "beep" | at noon ${AT}
Improved version of command #8425.
This way, the default browser is used, as opposed to Firefox.
If you are stuck behind a firewall and want to synchronize time with another server but you do not want to port forward NTP (which uses UDP) then this command is handy. It gets the time from a server and sets the local time. It is not that accurate but I can live with a second or so drift.
"infix" version in bash (4.x+)
Remove -v to make it silent.
BTW: The OP forgot to use "cat" and "nmap" ;-) I had a good laugh though.
QR codes are those funny square 2d bar codes that everyone seems to be pointing their smart phones at.
Try the following...
qrurl http://xkcd.com
Then open qr.*.png in your favorite image viewer.
Point your the bar code reader on your smart phone at the code, and you'll shortly be reading xkcd on your phone.
URLs are not the only thing that can be encoded by QR codes... short texts (to around 2K) can be encoded this way, although this function doesn't do any URL encoding, so unless you want to do that by hand it won't be useful for that.
This backup function preserve the file suffix allowing zsh suffix aliases and desktop default actions to work with the backup file too.