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FizzBuzz in one line of Bash
The (in)famous "FizzBuzz" programming challenge, answered in a single line of Bash code. The "|column" part at the end merely formats the output a bit, so if "column" is not installed on your machine you can simply omit that part. Without "|column", the solution only uses 75 characters. The version below is expanded to multiple lines, with comments added. for i in {1..100} # Use i to loop from "1" to "100", inclusive. do ((i % 3)) && # If i is not divisible by 3... x= || # ...blank out x (yes, "x= " does that). Otherwise,... x=Fizz # ...set x to the string "Fizz". ((i % 5)) || # If i is not divisible by 5, skip (there's no "&&")... x+=Buzz # ...Otherwise, append (not set) the string "Buzz" to x. echo ${x:-$i} # Print x unless it is blanked out. Otherwise, print i. done | column # Wrap output into columns (not part of the test).

Diff 2 file struct - Useful for branch diff and jars diff(uncompressed)
This is usefull to diff 2 paths in branches of software, or in different versions of a same zip file. So you can get the real file diff.

Remove all subversion files from a project recursively
This command will remove all .svn folder from your project if you need to manual remove the subversion files.

Make a server's console beep when the network is down
This is like ping -a, but it does the opposite. It alerts you if the network is down, not up. Note that the beep will be from the speaker on the server, not from your terminal. Once a second, this script checks if the Internet is accessible and beeps if it is not. I define the Net as being "UP", if I can ping Google's public DNS server (8.8.8.8), but of course you could pick a different static IP address. I redirect the beep to /dev/console so that I can run this in the background from /etc/rc.local. Of course, doing that requires that the script is run by a UID or GID that has write permissions to /dev/console (usually only root). Question: I am not sure if the -W1 flag works under BSD. I have only tested this under GNU/Linux using ping from iputils. If anybody knows how portable -W is, please post a comment.

Uptime in minute
Want to run scripts/programs in the system after starting X minute [ For letting the system to free ]? This will give uptime in minute.

Retrieve a random command from the commandlinefu.com API
Seeing that we get back plain text anyway we don't need lynx. Also the sed-part removes the credit line.

Multi-thread any command
For instance: $ find . -type f -name '*.wav' -print0 |xargs -0 -P 3 -n 1 flac -V8 will encode all .wav files into FLAC in parallel. Explanation of xargs flags: -P [max-procs]: Max number of invocations to run at once. Set to 0 to run all at once [potentially dangerous re: excessive RAM usage]. -n [max-args]: Max number of arguments from the list to send to each invocation. -0: Stdin is a null-terminated list. I use xargs to build parallel-processing frameworks into my scripts like the one here: http://pastebin.com/1GvcifYa

List all execs in $PATH, usefull for grepping the resulting list
While it seems (to me at least) a little counter-intuitive to filter on name first, this requires less work for find, as it allows it to immediately discount any files that do not match the name directly from the directory listing on disk. Querying against file attributes requires reading the file attributes, which is performed for all files matching any name based predicates.

Save a file you edited in vim without the needed permissions (no echo)
Write a file you edited in Vim but that you do not have the permissions to write to (unless you use sudo.) Same as #1204 but without the echo to stdout that I find annoying.

Use a var with more text only if it exists
See "Parameter Expansion" in the bash manpage. They refer to this as "Use Alternate Value", but we're including the var in the at alternative.


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