Commands by puddleglum (2)

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Graphical tree of sub-directories
Prints a graphical directory tree from your current directory

Detect illegal access to kernel space, potentially useful for Meltdown detection
Based on capsule8 agent examples, not rigorously tested

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

do 'foo' until it exits successfully, pausing in between crashes
restart a buggy script when it dies. works great for "git svn fetch", which leaks memory like a sieve and eventually dies...making you restart it.

find your release version of your ubuntu / debian distro

Recursive search and replace (with bash only)
Replaces a string matching a pattern in one or several files found recursively in a particular folder.

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"

Drop or block attackers IP with null routes
Someone might attack on your system. You can drop attacker IP using IPtables. However, you can use route command to null route unwanted traffic. A null route (also called as blackhole route) is a network route or kernel routing table entry that goes nowhere. Matching packets are dropped (ignored) rather than forwarded, acting as a kind of very limited firewall. The act of using null routes is often called blackhole filtering.

ls -hog --> a more compact ls -l
I often deal with long file names and the 'ls -l' command leaves very little room for file names. An alternative is to use the -h -o and -g flags (or together, -hog). * The -h flag produces human-readable file size (e.g. 91K instead of 92728) * The -o suppresses the owner column * The -g suppresses the group column Since I use to alias ll='ls -l', I now do alias ll='ls -hog'

ROT13 whole file in vim.
gg puts the cursor at the begin g? ROT13 until the next mov G the EOF


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