Optionally, one can use {1..50} instead of seq. E.g. for i in {1..50} ; do echo Iteration $i ; done Show Sample Output
This command converts a MySQL query directly into a .csv (Comma Seperated Value)-file. Show Sample Output
Set an alarm to starts in specific time. Show Sample Output
When you use a "for" construct, it cycles on every word. If you want to cycle on a line-by-line basis (and, well, you can't use xargs -n1 :D), you can set the IFS variable to . Show Sample Output
A little bash daemon
Very useful for interactive scripts where you would like to return the terminal contents to its original state before the script was run. This would be similar to how vi exits and returns you to your original terminal screen.
Save and clear the terminal contents with:
tput smcup
Execute some commands, then restore the saved terminal contents with:
tput rmcup
Joker wants an email if the Brand X server is down. Set a cron job for every 5 mins with this line and he gets an email when/if a ping takes longer than 3 seconds. Show Sample Output
This can show all ls colors, with a demo.
The above is just a prove of concept based around the nested bash substitution. This could be useful in situations where you're in a directory with many filetypes but you only want to convert a few.
for f in *.bmp *.jpg *.tga; do convert $f ${f%.*}.png; done
or you can use ls | egrep to get more specific... but be warned, files with spaces will cause a ruckus with expansion but the bash for loop uses a space delimited list.
for f in $(ls | egrep "bmp$|jpg$|tga$"); do convert $f ${f%.*}.png; done
I'm guessing some people will still prefer doing it the sed way but I thought the concept of this one was pretty neat. It will help me remember bash substitutions a little better :-P
Show Sample Output
A bash version.
If your admin has disabled Apache's directory index feature but you want to have a cheap way to enable it for one folder, this command will just create an index.html file with a link to each file in the directory (including the index.html file, which is not ideal but makes the command much simpler). The HTML isn't even remotely compliant, but it could easily be improved on. Also, the command needs to be run each time a file is added or removed to update the index.html file. Show Sample Output
Can be used for command line parameters too.
If you have a more complicated way of entering values (validation, GUI, ...), then write a function i.e. EnterValue() that echoes the value and then you can write:
param=${param:-$(EnterValue)}
I find it useless but definitely simpler than #9230 Show Sample Output
Found here: http://ubuntuforums.org/showthread.php?t=589975
Certain Flash video players (e.g. Youtube) write their video streams to disk in /tmp/ , but the files are unlinked. i.e. the player creates the file and then immediately deletes the filename (unlinking files in this way makes it hard to find them, and/or ensures their cleanup if the browser or plugin should crash etc.) But as long as the flash plugin's process runs, a file descriptor remains in its /proc/ hierarchy, from which we (and the player) still have access to the file. The method above worked nicely for me when I had 50 tabs open with Youtube videos and didn't want to have to re-download them all with some tool.
This creates a permanent stock ticker in the terminal. it has scrolling action and refreshes when each cycle is done to get the latest news.
Shell function which takes a bash command as its input, and displays the following formatted output: EXAMPLE: command OUTPUT: output from command Show Sample Output
If you have a file full of numbers written line by line, you can sum every line to get the total. With a file like this: 3443535 9878977 67554 987798 232324 you will got: 14610188
Return the current shell. It is better than print $SHELL which can sometimes return a false value. Show Sample Output
This will cause your machine to INSTANTLY reboot. No un-mounting of drives or anything. Very handy when something has gone horribly wrong with your server in that co-location facility miles away with no remote hands! Suspect this works with all 2.2, 2.4 and 2.6 Linux kernels compiled with magic-syskey-request support.
The Festival Speech Synthesis System converts text into sound. Or: links -dump http://youfavoritewebsite.com | festival --tts Show Sample Output
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