Commands by gtmanfred (2)

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Simple Comment an entire file
With this simple sed command we can easily comment and entire file.

Encode png's into blu-ray format
This command takes a set of images (from a render, for example), and converts them into a format conforming to the Blu-ray spec, or at least the version on the Wikipedia page.

Cut out a piece of film from a file. Choose an arbitrary length and starting time.
With: -vcodec, you choose what video codec the new file should be encoded with. Run ffmpeg -formats E to list all available video and audio encoders and file formats. copy, you choose the video encoder that just copies the file. -acodec, you choose what audio codec the new file should be encoded with. copy, you choose the audio encoder that just copies the file. -i originalfile, you provide the filename of the original file to ffmpeg -ss 00:01:30, you choose the starting time on the original file in this case 1 min and 30 seconds into the film -t 0:0:20, you choose the length of the new film newfile, you choose the name of the file created. Here is more information of how to use ffmpeg: http://www.ffmpeg.org/ffmpeg-doc.html

archlinux:Delete packages from pacman cache that are older than 7 days
Sometimes my /var/cache/pacman/pkg directory gets quite big in size. If that happens I run this command to remove old package files. Packages that we're upgraded in last N days are kept in case you are forced to downgrade a specific package. The command is obviously Arch Linux related.

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

Bind a key with a command
the -x option is for binding to a shell command

Print line immediately before a matching regex.
Use this if you don't have access to GNU grep's -B option.

Calculate N!

Run the last command as root
this command also can run the last command as root what's more, sudo !-2 can run the second last command as root , and so on

Create a self-signed certificate for Apache Tomcat
Must be run as root. The 'tomcat' user must have access to the .keystore file. The key and keystore passwords must be the same. The password must be entered into the server.xml config file for Tomcat.


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