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Url Encode
Returns URL Encoded string from input ($1).

Infinite loop ssh

Using the urxvt terminal daemon
- for .xsession use - Advantages of running a urxvt daemon include faster creation time for terminal windows and a lot of saved memory. You can start new terminals as childs of urxvtd by typing urxvtc. Another advantage is, that background jobs are always owned by the urxvtd and will survive as long the daemon is running.

Delete empty directories recursively

Apply fade effect to a audio
fade [type] fade-in-length [stop-time [fade-out-length]] Apply a fade effect to the beginning, end, or both of the audio. An optional type can be specified to select the shape of the fade curve: q for quarter of a sine wave, h for half a sine wave, t for linear (`triangular') slope, l for logarithmic, and p for inverted parabola. The default is logarithmic. A fade-in starts from the first sample and ramps the signal level from 0 to full volume over fade-in-length sec? onds. Specify 0 seconds if no fade-in is wanted. For fade-outs, the audio will be truncated at stop-time and the signal level will be ramped from full volume down to 0 starting at fade-out-length seconds before the stop-time. If fade-out-length is not specified, it defaults to the same value as fade-in-length. No fade-out is performed if stop-time is not specified. If the file length can be determined from the input file header and length-changing effects are not in effect, then 0 may be specified for stop-time to indicate the usual case of a fade-out that ends at the end of the input audio stream. All times can be specified in either periods of time or sample counts. To specify time periods use the format hh:mm:ss.frac format. To specify using sample counts, specify the number of samples and append the letter `s' to the sample count (for example `8000s').

Print a list of installed Perl modules
This version works on an AIX system on which I have very limited permissions. The other version fails with "Can't open file /usr/opt/perl588/lib/site_perl/5.8.8/aix/auto/DBI/.packlist".

extract element of xml
poor man's xml parser :)

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).

draw line separator
Even shorter: $ seq -s '*' 120|tr -d '[0-9]'

View any archive
Part of the "atool" package.


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