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Reset hosed terminal,
stty sane resets the tty to basic usable function. The ^J is a newline -- sometimes CR/LF interpretation is broken so use the ^J explicitly.

Find last reboot time
Specific to OSX.

Create the four oauth keys required for a Twitter stream feed
Twitter stream feeds now require authentication. This command is the FIRST in a set of five commands you'll need to get Twitter authorization for your final Twitter command. *** IMPORTANT *** Before you start, you have to get some authorization info for your "app" from Twitter. Carefully follow the instructions below: Go to dev.twitter.com/apps and choose "Create a new application". Fill in the form. You can pick any name for your app. After submitting, click on "Create my access token". Keep the resulting page open, as you'll need information from it below. If you closed the page, or want to get back to it in the future, just go to dev.twitter.com/apps Now customize FIVE THINGS on the command line as follows: 1. Replace the string "Consumer key" by copying & pasting your custom consumer key from the Twitter apps page. 2. Replace the string "Consumer secret" by copying & pasting your consumer secret from the Twitter apps page. 3. Replace the string "Access token" by copying & pasting your access token from the Twitter apps page. 4. Replace string "Access token secret" by copying & pasting your own token secret from the Twitter apps page. 5. Replace the string 19258798 with the Twitter UserID NUMBER (this is **NOT** the normal Twitter NAME of the user you want the tweet feed from. If you don't know the UserID number, head over to www.idfromuser.com and type in the user's regular Twitter name. The site will return their Twitter UserID number to you. 19258798 is the Twitter UserID for commandlinefu, so if you don't change that, you'll receive commandlinefu tweets, uhm... on the commandline :) Congratulations! You're done creating all the keys! Environment variables k1, k2, k3, and k4 now hold the four Twitter keys you will need for your next step. The variables should really have been named better, e.g. "Consumer_key", but in later commands the 256-character limit forced me to use short, unclear names here. Just remember k stands for "key". Again, remember, you can always review your requested Twitter keys at dev.twitter.com/apps. Our command line also creates four additional environment variables that are needed in the oauth process: "once", "ts", "hmac" and "id". "once" is a random number used only once that is part of the oauth procedure. HMAC is the actual key that will be used later for signing the base string. "ts" is a timestamp in the Posix time format. The last variable (id) is the user id number of the Twitter user you want to get feeds from. Note that id is ***NOT*** the twitter name, if you didn't know that, see www.idfromuser.com If you want to learn more about oauth authentication, visit oauth.net and/or go to dev.twitter.com/apps, click on any of your apps and then click on "Oauth tool" Now go look at my next command, i.e. step2, to see what happens next to these eight variables.

Find and display most recent files using find and perl
This pipeline will find, sort and display all files based on mtime. This could be done with find | xargs, but the find | xargs pipeline will not produce correct results if the results of find are greater than xargs command line buffer. If the xargs buffer fills, xargs processes the find results in more than one batch which is not compatible with sorting. Note the "-print0" on find and "-0" switch for perl. This is the equivalent of using xargs. Don't you love perl? Note that this pipeline can be easily modified to any data produced by perl's stat operator. eg, you could sort on size, hard links, creation time, etc. Look at stat and just change the '9' to what you want. Changing the '9' to a '7' for example will sort by file size. A '3' sorts by number of links.... Use head and tail at the end of the pipeline to get oldest files or most recent. Use awk or perl -wnla for further processing. Since there is a tab between the two fields, it is very easy to process.

Find usb device
I often use it to find recently added ou removed device, or using find in /dev, or anything similar. Just run the command, plug the device, and wait to see him and only him

Remove all cached images for icons related to your profile
Run inside Command Prompt (cmd.exe) as admin. Note that you must close explorer.exe first, and even so some files will not be deleted, will say "Access is denied." To definitely delete them enter with another admin user or from other operating system and access the drive.

Push a directory onto the stack
Use also with: Move to respective parameters == () { = +2; } === () { = +3; } ==== () { = +4; } Pop the last entry off the directory stack - () { popd ${1:+"$1"}; }

Realy remove file from your drive
This command remove a file from your filesystem like the normal rm command but instead of deleting only the inode information this also delete the data that was stored on blocks /!\ warning this may be long for large files

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.

Query well known ports list
Uses the file located in /etc/services


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