Commands by crazedsanity (4)

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Text to image with transparent background
Create transparent image to use as icon, watermark for other images, etc.

Find the package that installed a command

Get version of loaded kernel module
Returns the version of the kernel module specified as "MODULENAME", when available.

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

Execute a command without saving it in the history
Yes, by correctly setting the HIST* variables you can make certain commands not saved in history. But that's complicated and easy to make a mistake. If you set HISTFILE= to blank, nothing in your current shell session will be saved in history. Although this is not a precise answer to the subject, but it's very simple.

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

Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

Find files containing string and open in vim
I often use "vim -p" to open in tabs rather than buffers.

Find brute force attempts on SSHd
Searches the /var/log/secure log file for Failed and/or invalid user log in attempts.

converting vertical line to horizontal line


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