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Poor man's nmap for a class C network from rfc1918
What do you do when nmap is not available and you want to see the hosts responding to an icmp echo request ? This one-liner will print all hosts responding with their ipv4 address.

Show some trivia related to the current date
Contrary to logic, typing calendar won't show a calendar, that's the job of cal. Typing calendar will show some trivia related to the current date. Tested against many Linux distros and FreeBSD.

Write comments to your history.
A null operation with the name 'comment', allowing comments to be written to HISTFILE. Prepending '#' to a command will *not* write the command to the history file, although it will be available for the current session, thus '#' is not useful for keeping track of comments past the current session.

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

Show directories in the PATH, one per line
This version uses Pipes, but is easier for the common user to grasp... instead of using sed or some other more complicated method, it uses the tr command

Monitor open connections for httpd including listen, count and sort it per IP
It's not my code, but I found it useful to know how many open connections per request I have on a machine to debug connections without opening another http connection for it. You can also decide to sort things out differently then the way it appears in here.

Quickly share code or text from vim to others.
Sprunge.us is a code/text sharing site like pastebin, but it is easy to post stuff from the command line. $ How it works: $ :w !command In vim, w writes the current tab to a file when a filename is given afterwards, but if !command is given, the output is piped to the stdin of command. $curl -F "sprunge=

Find removed files still in use via /proc
Oracle DBA remove some logfiles which are still open by the database and he is complaining the space has not been reclaimed? Use the above command to find out what PID needs to be stopped. Or alternatively recover the file via: $ cp /proc/pid/fd/filehandle /new/file.txt

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

Upgrade all perl modules via CPAN


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