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Functions

Commands tagged date from sorted by
Terminal - Commands tagged date - 101 results
sajb {$ip="192.168.100.1";$old=0;while(1){$up=test-connection -quiet -count 1 $ip;if($up-ne$old){$s=(date -u %s).split('.')[0]+' '+(date -f s).replace('T',' ')+' '+$ip+' '+$(if($up){'Up'}else{'Down'});echo $s|out-file -a $home\ping.txt;$old=$up}sleep 10}}
0

IMPORTANT: You need Windows PowerShell to run this command - in your Windows Command Prompt, type

powershell

Uses sajb to start a PowerShell background job that pings an IP host every 10 seconds.

Any changes in the host's Up/Down state is time-stamped and logged to a file.

Date/time stamps are logged in two formats: Unix and human-readable.

A while(1) loop repeats the test every 10 seconds by using the sleep command.

See the Sample Output for more detail.

I use this command to log Up/Down events of my Motorola SB6141 cable modem (192.168.100.1).

To end the logging, close the PowerShell window or use the "exit" command.

echo "obase=2;$((($(date +%s)-$(date +%s -d YYYY-MM-DD))/86400))" | bc
2015-10-19 15:40:32
User: flatcap
Functions: echo
2

Print out your age in days in binary.

Today's my binary birthday, I'm 2^14 days old :-)

.

This command does bash arithmatic $(( )) on two dates:

Today: $(date +%s)

Date of birth: $(date +%s -d YYYY-MM-DD)

The dates are expressed as the number of seconds since the Unix epoch (Jan 1970),

so we devide the difference by 86400 (seconds per day).

.

Finally we pipe "obase=2; DAYS-OLD" into bc to convert to binary.

(obase == output base)

D="$(date "+%F %T.%N")"; [COMMAND]; find . -newermt "$D"
2015-10-15 21:09:54
User: flatcap
Functions: find
2

Often you run a command, but afterwards you're not quite sure what it did.

By adding this prefix/suffix around [COMMAND], you can list any files that were modified.

.

Take a nanosecond timestamp: YYYY-MM-DD HH:MM:SS.NNNNNNNNN

date "+%F %T.%N"

.

Find any files that have been modified since that timestamp:

find . -newermt "$D"

.

This command currently only searches below the current directory.

If you want to look elsewhere change the find parameter, e.g.

find /var/log . -newermt "$D"
ssh(){ L="\$HOME/logs/$(date +%F_%H:%M)-$USER";/usr/bin/ssh -t "$@" "mkdir -p \"${L%/*}\";screen -xRRS $USER script -f \"$L\"";}
2015-10-14 13:14:29
User: flatcap
Functions: ssh
3

A wrapper around ssh to automatically provide logging and session handling.

This function runs ssh, which runs screen, which runs script.

.

The logs and the screen session are stored on the server.

This means you can leave a session running and re-attach to it later, or from another machine.

.

.

Requirements:

* Log sessions on a remote server

* Transparent - nothing extra to type

* No installation - nothing to copy to the server beforehand

.

Features:

* Function wrapper delegating to ssh

- so nothing to remember

- uses .ssh/config as expected

- passes your command line option to ssh

* Self-contained: no scripts to install on the server

* Uses screen(1), so is:

- detachable

- re-attachable

- shareable

* Records session using script(1)

* Configurable log file location, which may contain variables or whitespace

L="$HOME" # local variable

L="\$HOME" # server variable

L="some space"

.

Limitations:

* Log dir/file may not contain '~' (which would require eval on the server)

.

.

The sessions are named by the local user connecting to the server.

Therefore if you detach and re-run the same command you will reconnect to your original session.

If you want to connect/share another's session simply run:

USER=bob ssh [email protected]

.

The command above is stripped down to an absolute minimum.

A fully expanded and annotated version is available as a Gist (git pastebin):

https://gist.github.com/flatcap/3c42326abeb1197ee714

.

If you want to add timing info to script, change the command to:

ssh(){ L="\$HOME/logs/$(date +%F_%H:%M)-$USER";/usr/bin/ssh -t "$@" "mkdir -p \"${L%/*}\";screen -xRRS $USER script --timing=\"$L-timing\" -f \"$L\"";}
echo FileName | perl -nlE'sleep 1 while time-(stat)[10]<10' && echo DONE
2015-05-09 14:58:41
User: pung96
Functions: echo perl
0

perl version of "Wait for file to stop changing"

When "FileName" has not been changed for last 10 seconds, then print "DONE"

"10" in "(stat)[10]" means ctime.

One have other options like atime, mtime and others. http://perldoc.perl.org/functions/stat.html

while [ $(( $(date +%s) - $(stat -c %Y FILENAME) )) -lt 10 ]; do sleep 1; done; echo DONE
2015-05-09 12:30:13
User: flatcap
Functions: date echo sleep stat
3

This loop will finish if a file hasn't changed in the last 10 seconds.

.

It checks the file's modification timestamp against the clock.

If 10 seconds have elapsed without any change to the file, then the loop ends.

.

This script will give a false positive if there's a 10 second delay between updates,

e.g. due to network congestion

.

How does it work?

'date +%s' gives the current time in seconds

'stat -c %Y' gives the file's last modification time in seconds

'$(( ))' is bash's way of doing maths

'[ X -lt 10 ]' tests the result is Less Than 10

otherwise sleep for 1 second and repeat

.

Note: Clever as this script is, inotify is smarter.

debugfs -R "stat <$(stat --printf=%i filename)>" /dev/sdaX | grep crtime
2015-04-09 01:23:56
User: pggx999
Functions: debugfs grep
3

Return the creation date of a file on ext2, 3, 4 filesystems, because stat command won't show it.

Useful on ubuntu, debian, and else

date -r 1390196676
function findOlderThan () { find . -mmin -$((($(date "+%s") - $(stat -c %Y $1))/60)) -type f ; }
2014-08-29 17:52:34
User: RobertDeRose
Functions: date find stat
Tags: find date stat
0

This function will find the modification time in unix_time of the given file, then calculate the number of minutes from now to then and then find all files modified in that range.

YEAR=2015; echo Jul $(ncal 7 $YEAR | awk '/^Fr/{print $NF}')
2014-08-17 11:12:09
User: andreasS
Functions: awk echo
Tags: awk date
0

Calculate the date of Sysadmin day (last Friday of July) of any given year

YEAR=2015; date -d${YEAR}0801-$(date -d${YEAR}0801+2days +%u)days +%b\ %e
2014-08-17 11:06:25
User: andreasS
Functions: date
Tags: date
0

Calculate Sysadmin day of any given year using 2 `date`. Code based on http://stackoverflow.com/a/5656859/196133

YEAR=2015; ncal 7 $YEAR | sed -n 's/^Fr.* \([^ ]\+\) *$/Jul \1/p'
2014-08-17 11:04:02
User: andreasS
Functions: sed
Tags: sed date
0

Calculate the date of Sysadmin day (last Friday of July) of any given year

echo {-1..-5}days | xargs -n1 date +"%Y-%m-%d" -d
alias t__s='date "+%FT%T"'
2014-03-06 04:37:55
User: UncleLouie
Functions: alias
0

This can be easier to look at in ls output. Not as clean as +%Y%m%dT%H%M%S, but quicker to write.

date -u `ssh [email protected] date -u '+%m%d%H%M%Y.%S'`
2014-02-10 03:11:14
User: scruss
Functions: date
0

Useful if localhost is a small machine running BusyBox, which uses a slightly unusual format to set the date. Remotehost can be pretty much any Linux machine, including one running BusyBox. Uses UTC for portability.

touch -r "source_file" "destination_file"
sudo tar -zcvf $(hostname)-etc-back-`date +%d`-`date +%m`-`date +%y`.tar.gz /etc && sudo chown $USER:$USER $(hostname)-etc-back*
2013-08-18 12:49:11
User: thanosme
Functions: chown sudo tar
Tags: backup tar date
0

Back up /etc directory with a name based on the current date and the hostname of the machine, then chown the file for the current user for use.

git log | grep Date | awk '{print " : "$4" "$3" "$6}' | uniq -c
sudo cp /usr/share/zoneinfo/Europe/Paris /etc/localtime
ls -lT -rt | grep "^-" | awk 'BEGIN {START=2002} (START <= $9){ print $10 ;START=$9 }' | tail -1
2013-02-24 23:39:22
User: Glamdring
Functions: awk grep ls tail
Tags: ls date osx
0

On the Mac, the 'ls' function can sort based on month/day/time, but seems to lack ability to filter on the Year field (#9 among the long listed fields). The sorted list continuously increases the 'START' year for the most recently accessed set of files. The final month printed will be the highest month that appeared in that START year. The command does its magic on the current directory, and suitably discards all entries that are themselves directories. If you expect files dating prior to 2002, change the START year accordingly.

if date -d 2006-10-10 >> /dev/null 2>&1; then echo 1; else echo 0; fi
2013-01-10 10:35:15
Functions: date echo
0

On CentOS at least, date returns a boolean for the common date string formats, including YYYY-MM-DD. In the sample output, you can see various invalid dates returning 0 whereas a simple regex check would return 1 for the invalid dates.

-d, --date=STRING display time described by STRING, not `now'

The version of date on OS X does not appear to have this same option.

date +%:z
buf () { oldname=$1; if [ "$oldname" != "" ]; then datepart="$(date +%Y-%m-%d).bak"; firstpart=`echo $oldname | cut -d "." -f 1`; newname=`echo $oldname | sed s/$firstpart/$firstpart.$datepart/`; cp -iv ${oldname} ${newname}; fi }
2012-08-15 08:31:44
User: juliushibert
Functions: cp cut sed
1

Appends the input file with the date format YYYY-MM-DD.bak. Also runs silently if you remove the -v on the cp at the end of the function.

echo 00:29:36 | sed s/:/*60+/g | bc
datefudge "2012-12-01 12:00" date