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This script creates date based backups of the files. It copies the files to the same place the original ones are but with an additional extension that is the timestamp of the copy on the following format: YearMonthDay-HourMinuteSecond
already described on the other two versions, this one uses ascii characters on game style to display elapsed time.
Variation of the theme, this one blinks in low profile on top level of X, ie, it is visible, indeed small.
Try changing fonts and sizes of osd_cat
Works on real time clock, unix time based, decrementing the actual time from initial time saved in an environment variable exported to child process inside watch
Shows elapsed time from start of script in hh:mm:ss format
Non afected by system slow down due to the use of date.
See: http://imgur.com/JgjK2.png for example.
Do some serious benchmarking from the commandline. This will write to a file with the time it took to compress n bytes to the file (increasing by 1).
Run:
gnuplot -persist <(echo "plot 'lzma' with lines, 'gzip' with lines, 'bzip2' with lines")
To see it in graph form.
The "-d" option for gnu's "date" command can calculate positive or negative offset from any time, including "now". You can even specify a source timezone (the output timezone can be set with the TZ environment variable). Useful! Fun! Not very well documented!
This is very useful if you need to show someone some text from a distance. (Like someone standing over your shoulder...)
I'd recommend aliasing it to something like:
alias osd_cat="osd_cat -o 400 -s 8 -c blue -d 60 -f -*-bitstream\ vera\ sans-*-*-*--200-*-*-*-*-*-*-*"
xosd is the utility that provides osd_cat.
This will log your internet download speed.
You can run
gnuplot -persist <(echo "plot 'bps' with lines")
to get a graph of it.
The end of unix time and the 32bit era will be Tue Jan 19 03:14:07 UTC 2038
.
date -ud @$[2**31]
date: invalid date `@2147483648'
.
In 64bit you have much longer, at least to:
date -ud @$[2**55]
Sun Jun 13 06:26:08 UTC 1141709097
This is the same command as this one, but for OS X.
This is the same command as this one, but for OS X.
Use `zless` to read the content of your *rss.gz file:
zless commandlinefu-contribs-backup-2009-08-10-07.40.39.rss.gz
Tres lineas en un shell script para copiar la base de datos diaramente
prints out the time for the timezone specified in $offsetutc. So you have less to think about things like: "I'm in utc+4 and my friend in utc-7, can I call him now or will I wake him?"
Note: $offsetutc should be an integer between -12 and 12.
It will create a backup of the filename. The advantage is that if you list the folder the backups will be sorted by date. The command works on any unix in bash.
A quick and simple way of outputting the start and end date of a certificate, you can simply use 'openssl x509 -in xxxxxx.crt -noout -enddate' to output the end date (ex. notAfter=Feb 01 11:30:32 2009 GMT) and with the date command you format the output to an ISO format.
For the start date use the switch -startdate and for end date use -enddate.
Performs a mysqldump and gzip-compresses the output file with a timestamp in the resulting dump file. Inspect the file for integrity or fun with this command afterward, if you desire:
zcat mysqldump-2009-06-12-07.41.01.tgz | less
With this command you can get a previous or future date or time. Where can you use this? How about finding all files modified or created in the last 5 mins?
touch -t `echo $(date -d "5 minute ago" "+%G%m%d%H%M.%S")` me && find . -type f -newer me
List all directories created since last week?
touch -t `echo $(date -d "1 week ago" "+%G%m%d%H%M.%S")` me && find . -type d -cnewer me
I'm sure you can think of more ways to use it. Requires coreutils package.
Important to know: a valid date will return 0, otherwise 1!
Not a discovery but a useful one nontheless.
In the above example date format is 'yyyymmdd'. For other possible formats see 'man date'.
This command can be also very convenient when aliased to some meaningful name:
alias mkdd='mkdir $(date +%Y%m%d)'