Commands by vaaclav (3)

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search installed files of package, that doesn't remember his name well. On rpm systems
rpm, sometimes, is not wildcard friendly. To search files installed from package this could be useful. change PACKAGENAME to any package do you want to search

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

Commandline document conversion with Libreoffice
In this example, the docx gets converted to Open Document .odt format. For other formats, you'll need to specify the correct filter (Hint: see "Comments" link below for a nice list).

Multiple variable assignments from command output in BASH
It's quite easy to capture the output of a command and assign it in a shell's variable: $ day=$(date +%d) $ month=$(date +%m) But, what if we want to perform the same task with just one program invocation? Here comes the power of eval! date(1) outputs a string like "day=29; month=07; year=11" (notice the semicolons I added on purpose at date's custom output) which is a legal shell line. This like is then parsed and executed by the shell once again with the help of eval. Just setting 3 variables! Inspired by LinuxJournal's column "Dave Taylor's Work the Shell".

du and sort to find the biggest directories in defined filesystem
This command give a human readable result without messing up the sorting.

check open ports (both ipv4 and ipv6)

Selecting a random file/folder of a folder
Also looks in subfolders

Do the last command, but say 'y' to everything
I doubt this works with other than bash, but then again, I havent tried. The 'yes' utility is very simple, it outputs a hell of a lot of 'y's to standard input. The '!!' command means 'the last command'. So this one-lines inputs a lot of y's into the last command, aggressively agreeing to everything. For instance, when doing apt-get.

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Sort files in folders alphabetically
Creates one letter folders in the current directory and moves files with corresponding initial in the folder.


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