Commands using tail

Often you need to find the files that are taking up the most disk space in order to free up space asap. This script can be run on the enitre filesystem as root or on a home directory to find the largest files.

this adds a random color to your prompt and the external ip.

useful if you are using multiple mashines with the same hostname.

The given example collects output of the tail command: Whenever a line is emitted, further lines are collected, until no more output comes for one second. This group of lines is then sent as notification to the user.

You can test the example with

Tail curren postfix maillog.

tail -c 1 "$1" returns the last byte in the file.

Command substitution deletes any trailing newlines, so if the file ended in a newline $(tail -c 1 "$1") is now empty, and the -z test succeeds.

However, $a will also be empty for an empty file, so we add -s "$1" to check that the file has a size greater than zero.

Finally, -f "$1" checks that the file is a regular file -- not a directory or a socket, etc.

You can use this one-liner for a quick and dirty (more customizable) alternative to the watch command. The keys to making this work: everything exists in an infinite loop; the loop starts with a clear; the loop ends with a sleep. Enter whatever you'd like to keep an eye on in the middle.

Download colorizer by @raszi @ http://github.com/raszi/colorize

git log --format=%H | tail -1 doesn't work anymore

'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 :

http://blog.interlinked.org/tutorials/rsync_time_machine.html

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.

Tail all logs that are opened by all java processes. This is helpful when you are on a new environment and you do not know where the logs are located. Instead of java you can put any process name. This command does work only for Linux.

The list of all log files opened by java process:

Can anyone make a shorter one?

This doesn't work:

requires "youtube-dl" -- sure you can do this with wget and some more obscurity but why waste your time when this great tool is available?

the guts consist of mplayer converting a video to a gif -- study this command and read the man page for more information

generates a 6 second gif starting at 23 seconds of play time at 5 fps and a scale of 400x300

start time (-ss)/end time (-endpos) formats: 00:00:00.000

end time should be relative to start time, not absolute. i.e. -endpos 5 == seconds after 0:42 = 0:47 end point

play with fps and scale for lower gif sizes

the subshell is a solution for the -b flag on youtube-dl which downloads the best quality video, sometimes, which can be various video formats $(ls ${url##*=}*| tail -n1)

this command shows the space used in postgres directory.

using tail first won't do it because tail counts from the bottom of the file. You could do it this way but I don't suggest it

tail -n X | head -n 1

prints a specific line, where X is the line number

Instead of having someone else read you the Digg headlines, Have OSX do it. Requires Curl+Sed+Say. This could probably be easily modified to use espeak for Linux.

This only works in bash

The -s option allows you to specify the update interval

Plays the mp3 stream of The Current as a background job. When you are done run:

then to exit

Quite possible with Growl for mac I'd guess, although have not tried.

Libnotify needed for notification, stream will still work otherwise