Commands using dirname (22)

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Parse a quoted .csv file
The $2, $3, $4 fields are arbitrary but note that the first field starts from $2 and the last field is $NF-1. This is due to the fact that the leading and trailing quotes are treated as field delimiters.

Create Encrypted WordPress MySQL Backup without any DB details, just the wp-config.php
The coolest way I've found to backup a wordpress mysql database using encryption, and using local variables created directly from the wp-config.php file so that you don't have to type them- which would allow someone sniffing your terminal or viewing your shell history to see your info. I use a variation of this for my servers that have hundreds of wordpress installs and databases by using a find command for the wp-config.php file and passing that through xargs to my function.

Bypass 1000 Entry limit of Active Directory with ldapsearch
That command bypass the entry limit specifing page results size, when the search arrive to the limit ldapsearch magically reiterate it from the last entry.

exit if another instance is running

launch bash without using any letters
I don't know why anyone would use this, I was just messing around tonight and managed to start bash without using any letters and thought I would share. It's pretty simple, first it tries to execute "-" redirecting stderr to stdout which prints the error "bash: -: command not found" to standard output, then I try to execute "bash: -: command not found" which produces the output "bash: bash: -: command not found: command not found". lastly, (on the other side of the semicolon) I use the underscore environment variable which refers to the last command run ("bash: -: command not found") and take out everything after the first ":" character using brace expressions and your left with "bash"

List available upgrades from apt (package names only)
Usefull if you only want to see the package names, or if you want to use them in a script.

DVD ripping with ffmpeg
To rip DVD movie to ogg format using ffmpeg, follow these steps. 1) find the vob files on the mounted video DVD in VIDEO_TS that stores the movie itself. There would be a few other VOB files that stores splash screen or special features, the vob files for the movie itself can be identified by its superior size. You can verify these vob files by playing them directly with a player (e.g. mplayer) 2) concatenate all such vob files, pipe to ffmpeg 3) calculate the video size and crop size. The ogg video size must be multiple of 16 on both width and height, this is inherit limitation of theora codec. In my case I took 512x384. The -vcodec parameter is necessary because ffmpeg doesn't support theora by itself. -acodec is necessary otherwise ffmpeg uses flac by default.

Get the 10 biggest files/folders for the current direcotry

Start a HTTP server which serves Python docs
I use this command to start a local Python document server over HTTP port 8888.

computes the most frequent used words of a text file
using $ cat WAR_AND_PEACE_By_LeoTolstoi.txt | tr -cs "[:alnum:]" "\n"| tr "[:lower:]" "[:upper:]" | sort -S16M | uniq -c |sort -nr | cat -n | head -n 30 ("sort -S1G" - Linux/GNU sort only) will also do the job but as some drawbacks (caused by space/time complexity of sorting) for bigger files...


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