Commands by pabloab (4)

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Show current working directory of a process

Calculate days on which Friday the 13th occurs (inspired from the work of the user justsomeguy)
Friday is the 5th day of the week, monday is the 1st. Output may be affected by locale.

A fun thing to do with ram is actually open it up and take a peek. This command will show you all the string (plain text) values in ram

Rename files in batch

Show demo of toilet fonts
Lists a sample of all installed toilet fonts

repeat any string or char n times without spaces between
(here is character '+' repeated 80 times) Sometimes needed to enhance the title of the script.

Grab an interface's IP from ifconfig without screen clutter
Sometimes, you don't really care about all the other information that ifconfig spits at you (however useful it may otherwise be). You just want an IP. This strips out all the crap and gives you exactly what you want.

list all file extensions in a directory
... plus do a sort according frequency

Convert CSV to JSON
Replace 'csv_file.csv' with your filename.

Add directory to $PATH if it's not already there
Sometimes in a script you want to make sure that a directory is in the path, and add it in if it's not already there. In this example, $dir contains the new directory you want to add to the path if it's not already present. There are multiple ways to do this, but this one is a nice clean shell-internal approach. I based it on http://stackoverflow.com/a/1397020. You can also do it using tr to separate the path into lines and grep -x to look for exact matches, like this: $ if ! $(echo "$PATH" | tr ":" "\n" | grep -qx "$dir") ; then PATH=$PATH:$dir ; fi which I got from http://stackoverflow.com/a/5048977. Or replace the "echo | tr" part with a shell parameter expansion, like $ if ! $(echo "${PATH//:/$'\n'}" | grep -qx "$dir") ; then PATH=$PATH:$dir ; fi which I got from http://www.commandlinefu.com/commands/view/3209/. There are also other more regex-y ways to do it, but I find the ones listed here easiest to follow. Note some of this is specific to the bash shell.


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