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Every new command is wrapped in a tweet and posted to Twitter. Following the stream is a great way of staying abreast of the latest commands. For the more discerning, there are Twitter accounts for commands that get a minimum of 3 and 10 votes - that way only the great commands get tweeted.
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If you don't have netcat, you can use curl.
Good when firewalled and only in need of a reasonable accurate time.
Use a fast responding web server.
That works in all softs, CLI or GUI... I don't want to waste time to all the time typing the same stuff . So, I have that command in my window manager shortcuts ( meta+l ). All the window managers have editable shortcuts AFAIK. If not, or you don't want to use it that way, you can easily use the xbindkeys soft.
I you're using kde4, you can run :
then open "inputs actions" and create a new shortcut.
For Gnome take a look there : http://www.cyberciti.biz/faq/howto-create-keyboard-shortcuts-in-gnome/
A more advanced one, with strings and newlines :
xvkbd -xsendevent -text "---8<-----\nToday date is: $(date +%Y%m%d)\n---8<-----"
For complicated or long paste, you can feed xvkbd with a file :
xvkbd -xsendevent -file <file>
You can simulate ^C ( control+c ) too or others combinations of keys :
xvkbd -text "\C\Ac"
There's no man page nor help ( On my Archlinux distro ), but you can see online doc there : http://homepage3.nifty.com/tsato/xvkbd/
Requires the date command. This also works with some other comics. Here's a bash script that displays daily Garfield, Id, and Andy Capp:
Not perl but shorter.
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
A shell function using perl to easily convert Unix-time to text.
Put in in your ~/.bashrc or equivalent.
Tested on Linux / Solaris Bourne, bash and zsh. using perl 5.6 and higher.
(Does not require GNU date like some other commands)
this works on Solaris, so not better than the "only-GNU"-tool :-(
I think, there is no one-liner for this, that will work on all *nix-es
Only shows files with actual changes to text (excluding whitespace). Useful if you've messed up permissions or transferred in files from windows or something like that, so that you can get a list of changed files, and clean up the rest.
Use `zless` to read the content of your *rss.gz file:
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.
This command displays a clock on your terminal which updates the time every second. Press Ctrl-C to exit.
A couple of variants:
A little bit bigger text:
watch -t -n1 "date +%T|figlet -f big"
You can try other figlet fonts, too.
Big sideways characters:
watch -n 1 -t '/usr/games/banner -w 30 $(date +%M:%S)'
This requires a particular version of banner and a 40-line terminal or you can adjust the width ("30" here).
Quick and easy way of validating a date format of yyyy-mm-dd and returning a boolean, the regex can easily be upgraded to handle "in betweens" for mm dd or to validate other types of strings, ex. ip address.
Boolean output could easily be piped into a condition for a more complete one-liner.
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)'
The British Government entering in the Gregorian era.
This example, for example, produces the output, "Fri Feb 13 15:26:30 EST 2009"
Echos the number of seconds from the current time till the specified time (Example in command is (2**31-1)) aka the Unix epoch. Just replace that number with the specified date (in seconds past Jan. 1st 1970) and it will return the seconds.
NOTE: Only works in bash
An improved version of http://www.commandlinefu.com/commands/view/1772/simple-countdown-from-a-given-date that uses Perl to pretty-print the output. Note that the GNU-style '--no-title' option has been replaced by its one-letter counterpart '-t'.