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Commands using date from sorted by
Terminal - Commands using date - 163 results
buf () { filename=$1; filetime=$(date +%Y%m%d_%H%M%S); cp ${filename} ${filename}_${filetime}; }
2010-12-14 13:19:52
User: dopeman
Functions: cp date
buf myfile.txt

This is useful when you are making small but frequent changes to a file. It keeps things organised and clear for another administrator to see what changed and at what time. An overview of changes can be deduced using a simple:

ls -ltr
read -a A <<<"8 9 5 10 6 0 3 11 7 4";B='.*.**..*....***';for C in $(date +"%H%M"|fold -w1);do echo "${B:${A[C]}:4}";done
for a in $(date +"%H%M"|cut -b1,2,3,4 --output-delimiter=" ");do case "$a" in 0)echo "....";;1)echo "...*";;2)echo "..*.";;3)echo "..**";;4)echo ".*..";;5)echo ".*.*";;6)echo ".**.";;7)echo ".***";;8)echo "*...";;9)echo "*..*";;esac;done
tail -f file | while read line; do echo -n $(date -u -Ins); echo -e "\t$line"; done
2010-11-19 10:01:57
User: hfs
Functions: date echo file read tail
Tags: tail date

This is useful when watching a log file that does not contain timestamps itself.

If the file already has content when starting the command, the first lines will have the "wrong" timestamp when the command was started and not when the lines were originally written.

alias tarred='( ( D=`builtin pwd`; F=$(date +$HOME/`sed "s,[/ ],#,g" <<< ${D/${HOME}/}`#-%F.tgz); tar --ignore-failed-read --transform "s,^${D%/*},`date +${D%/*}.%F`,S" -czPf "$F" "$D" &>/dev/null ) & )'
2010-11-18 06:24:34
User: AskApache
Functions: alias date tar

This is freaking sweet!!! Here is the full alias, (I didn't want to cause display problems on commandlinefu.com's homepage):

alias tarred='( ( D=`builtin pwd`; F=$(date +$HOME/`sed "s,[/ ],#,g" <<< ${D/${HOME}/}`#-%F.tgz); S=$SECONDS; tar --ignore-failed-read --transform "s,^${D%/*},`date +${D%/*}.%F`,S" -czPf "$"F "$D" && logger -s "Tarred $D to $F in $(($SECONDS-$S)) seconds" ) & )'

Creates a .tgz archive of whatever directory it is run from, in the background, detached from current shell so if you logout it will still complete. Also, you can run this as many times as you want, if the archive .tgz already exists, it just moves it to a numbered backup '--backup=numbered'. The coolest part of this is the transformation performed by tar and sed so that the archive file names are automatically created, and when you extract the archive file it is completely safe thanks to the transform command.

If you archive lets say /home/tombdigger/new-stuff-to-backup/ it will create the archive /home/#home#tombdigger#new-stuff-to-backup#-2010-11-18.tgz Then when you extract it, like tar -xvzf #home#tombdigger#new-stuff-to-backup#-2010-11-18.tgz instead of overwriting an existing /home/tombdigger/new-stuff-to-backup/ directory, it will extract to /home/tombdigger/new-stuff-to-backup.2010-11-18/

Basically, the tar archive filename is the PWD with all '/' replaced with '#', and the date is appended to the name so that multiple archives are easily managed. This example saves all archives to your $HOME/archive-name.tgz, but I have a $BKDIR variable with my backup location for each shell user, so I just replaced HOME with BKDIR in the alias.

So when I ran this in /opt/askapache/SOURCE/lockfile-progs-0.1.11/ the archive was created at /askapache-bk/#opt#askapache#SOURCE#lockfile-progs-0.1.11#-2010-11-18.tgz

Upon completion, uses the universal logger tool to output its completion to syslog and stderr (printed to your terminal), just remove that part if you don't want it, or just remove the '-s ' option from logger to keep the logs only in syslog and not on your terminal.

Here's how my syslog server recorded this..

2010-11-18T00:44:13-05:00 gravedigger.askapache.com ( [user] [notice] (logger:) Tarred /opt/askapache/SOURCE/lockfile-progs-0.1.11 to /askapache-bk/tarred/#opt#SOURCE#lockfile-progs-0.1.11#-2010-11-18.tgz in 4 seconds


Really this is very robust and foolproof, the only issues I ever have with it (I've been using this for years on my web servers) is if you run it in a directory and then a file changes in that directory, you get a warning message and your archive might have a problem for the changed file. This happens when running this in a logs directory, a temp dir, etc.. That's the only issue I've ever had, really nothing more than a heads up.


This is a simple alias, and very useful as it works on basically every linux box with semi-current tar and GNU coreutils, bash, and sed.. But if you want to customize it or pass parameters (like a dir to backup instead of pwd), check out this function I use.. this is what I created the alias from BTW, replacing my aa_status function with logger, and adding $SECONDS runtime instead of using tar's --totals

function tarred ()


local GZIP='--fast' PWD=${1:-`pwd`} F=$(date +${BKDIR}/%m-%d-%g-%H%M-`sed -u 's/[\/\ ]/#/g'

[[ ! -r "$PWD" ]] && echo "Bad permissions for $PWD" 1>&2 && return 2;

( ( tar --totals --ignore-failed-read --transform "s@^${PWD%/*}@`date +${PWD%/*}.%m-%d-%g`@S" -czPf $F $PWD && aa_status "Completed Tarp of $PWD to $F" ) & )


#From my .bash_profile http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html

tar cfz backup-$(date --iso).tar.gz somedirs
date +"%V"
2010-11-17 14:59:31
User: SuperFly
Functions: date

Not as cool as the python example, but it still works.

wget -O xkcd_$(date +%y-%m-%d).png `lynx --dump http://xkcd.com/|grep png`; eog xkcd_$(date +%y-%m-%d).png
TZ="$tz_dest" date -d "$(TZ="$tz_orig" date -d "$tm")"
date | md5sum
date --date=yesterday +%Y%m%d
2010-09-08 12:29:31
User: vinayv
Functions: date
Tags: bash date

The "date' command has options to easily format the date, day, month, time, etc. But what if you want a relative date or time. Like, I wanted yesterday's date in a particular format. You may want the exact date of "2 months ago" or "-3 days" nicely formatted. For that, you can use this command. The --date option takes fuzzy parameters like the ones mentioned in the previous sentence.

0 0 * * 0 /usr/bin/mysqldump -uroot -p'<password>' data_base_name > /home/bob/XYZ_DB_BACKUP/$(date +\%Y-\%m-\%d_\%Hh\%M).sql
2010-09-02 20:07:07
User: dtolj
Functions: date

Create a cronjob that runs weekly to backup your database to a file.

jb() { if [ -z $1 ];then printf 'usage:\njb <"date and/or time"> <"commandline"> &\nsee parsedate(3) strftime(3)\n';else t1=$(date +%s); t2=$(date -d "$1" +%s) ;sleep $(expr $t2 - $t1);$2 ;fi ;}
2010-08-26 23:50:42
User: argv
Functions: date expr printf


jb "next sun 12pm" "/bin/sh ~you/1.sh" &

jb "2010-08-29 12:00:00" "~you/1.sh" &

jb "29aug2010 gmt" ". ~you/1.sh" &

jb 12:00p.m. "nohup ./1.sh" &

jb 1min "echo stop!" &


parsedate(3) strftime(3)

rsync -av --link-dest=$(ls -1d /backup/*/ | tail -1) /data/ /backup/$(date +%Y%m%d%H%M)/
2010-08-05 19:36:24
User: dooblem
Functions: date ls rsync tail
Tags: backup rsync

'data' is the directory to backup, 'backup' is directory to store snapshots.

Backup files on a regular basis using hard links. Very efficient, quick. Backup data is directly available.

Same as explained here :


in one line.

Using du to check the size of your backups, the first backup counts for all the space, and other backups only files that have changed.

ls -la | grep $(date +%Y-%m-%d) | egrep -v -e '\.{1,2}' | sed "s/.*\:[0-9]\{2\} \(.\+\)$/\\1/g"
truss date 2>&1 | awk '/^time/{print $3}'
TZ=PST8PDT+72 date '+%Y_%m_%d'
2010-07-02 00:29:27
Functions: date
Tags: date nongnu

This command prints the Date (Not time) from 3 days ago (72 hours ago).

This works on systems without GNU date (MacOSX , Solaris, FreeBSD).

watch -tn1 'date -u +%T -d @$(expr $(date -d HH:MM +%s) - $(date +%s)) | toilet -f bigmono12'
2010-06-26 11:56:11
User: prayer
Functions: date expr watch
Tags: date time

Change HH:MM with your target time.

This is for a Debian/Ubuntu GNU system. You need bash (package bash), date (package coreutils) and toilet (package toilet). Install with:

# apt-get install bash coreutils toilet toilet-fonts

sleep 8h && while [ 1 ] ; do date "+Good Morning. It is time to wake up. The time is %I %M %p" | espeak -v english -p 0 -s 150 -a 100 ; sleep 1m; done
2010-06-23 17:34:54
User: copremesis
Functions: date sleep

This ran on a ubuntu box using espeak for speaking text with the bash shell. On a mac you should use 'say'. Also you can change your alarm interval and your snooze interval which are currently 8 hours and 1 minute. I would run this via cron yet it's easier to disable if you run it as a command like this :P

echo $((($(date +%s)-$(date +%s -d "march 1"))/86400))
2010-06-04 21:41:07
User: recursiverse
Functions: date echo

You can also do this for seconds, minutes, hours, etc... Can't use dates before the epoch, though.

H=$(until ([ $i -le 6 -a $i -gt 0 -o $i -le 23 -a $i -gt 21 ] ); do i=$(date +%N | cut -c8-10); done ; echo $i) ; M=$(until [ $i -le 59 ]; do i=$(date +%N | cut -c8-10); done ; echo $i) ; echo $M $H \* \* \* backup-rsync-push.sh
date MMDDhhmmYYYY
2010-05-29 08:26:13
User: christian773
Functions: date

date MMDDhhmmYYYY

date MMDDhhmm

# example 27.12.1975 08:00

date 122708001975

logfile=/var/log/gputemp.log; timestamp=$( date +%T );temps=$(nvidia-smi -lsa | grep Temperature | awk -F: ' { print $2 } '| cut -c2-4 | tr "\n" " ");echo "${timestamp} ${temps}" >> ${logfile}
say='festival --tts'; S=$(date +%s); echo $(echo $S | cut -b 1-1)" billion" | $say ; echo $(echo $S | cut -b 2-4 | sed 's/0*//')" million"| $say; echo $(echo $S | cut -b 5-7 | sed 's/0*//')" thousand"| $say
2010-05-28 09:19:24
User: rubo77
Functions: cut date echo sed

you will hear how many seconds since 1.1.1970 in english words with billions, millions and thousands.

this is very useful, if you want to get over to use the unixtimestamp instead of the 24 hour clock in your dayly life

touch file-$(date +%Y%m%d)