Commands by urdh (1)

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Getting ESP and EIP addresses from running processes
'ps' let you specify the format that you want to see on the output.

Generate random valid mac addresses
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copy root to new device
Clone a root partition. The reason for double-mounting the root device is to avoid any filesystem overlay issues. This is particularly important for /dev. Also, note the importance of the trailing slashes on the paths when using rsync (search the man page for "slash" for more details). rsync and bash add several subtle nuances to path handling; using trailing slashes will effectively mean "clone this directory", even when run multiple times. For example: run once to get an initial copy, and then run again in single user mode just before rebooting into the new disk. Using file globs (which miss dot-files) or leaving off the trailing slash with rsync (which will create /mnt/target/root) are traps that are easy to fall into.

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

Get current logged in users shortname

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"

Comment out all lines in a file beginning with string

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

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"

Convert multiple flac files to mp3
make sure that flac and lame are installed sudo apt-get install lame flac

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