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Find ulimit values of currently running process
When dealing with system resource limits like max number of processes and open files per user, it can be hard to tell exactly what's happening. The /etc/security/limits.conf file defines the ceiling for the values, but not what they currently are, while $ ulimit -a will show you the current values for your shell, and you can set them for new logins in /etc/profile and/or ~/.bashrc with a command like: $ ulimit -S -n 100000 >/dev/null 2>&1 But with the variability in when those files get read (login vs any shell startup, interactive vs non-interactive) it can be difficult to know for sure what values apply to processes that are currently running, like database or app servers. Just find the PID via "ps aux | grep programname", then look at that PID's "limits" file in /proc. Then you'll know for sure what actually applies to that process.

Log your internet download speed
This will log your internet download speed. You can run $gnuplot -persist

shell function which allows you to tag files by creating symbolic links directories in a 'tags' folder.
shell function which allows you to tag files by creating symbolic links directories in a 'tags' folder. The tag function takes a tag name as its first argument, then a list of files which take that tag. The directory $HOME/tags/tagname will then hold symbolic links to each of the tagged files. This function was modified from bartonski's (http://www.commandlinefu.com/commands/view/10216) inspired by tmsu (found at https://bitbucket.org/oniony/tmsu/wiki/Home) with readlink function by flxndn (http://www.commandlinefu.com/commands/view/10222). Example: $ tag dog airedale.txt .shizturc weimeraner.pl This will create $HOME/tags/dog which contains symbolic links to airedale.txt .shizturc and weimeraner.pl

Get AWS temporary credentials ready to export based on a MFA virtual appliance
You might want to secure your AWS operations requiring to use a MFA token. But then to use API or tools, you need to pass credentials generated with a MFA token. This commands asks you for the MFA code and retrieves these credentials using AWS Cli. To print the exports, you can use: `awk '{ print "export AWS_ACCESS_KEY_ID=\"" $1 "\"\n" "export AWS_SECRET_ACCESS_KEY=\"" $2 "\"\n" "export AWS_SESSION_TOKEN=\"" $3 "\"" }'` You must adapt the command line to include: * $MFA_IDis ARN of the virtual MFA or serial number of the physical one * TTL for the credentials

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.

List files accessed by a command
Can be run as a script `ftrace` if my_command is substrituted with "$@" It is useful when running a command that fails and you have the feeling it is accessing a file you are not aware of.

recursive remove all htm files

Extract audio from a video
With the -vn switch we make our intentions clear and ask FFmpeg not to bother itself with the video. Next we specify the audio codec copy, which tells FFmpeg to use the same codec to encode the audio, which it uses to decode it. To keep things simple, we'll just keep the sampling and bitrate values the same.

Generate a random password 30 characters long

Install pip with Proxy
Installs pip packages defining a proxy


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