Commands by flavioab (1)

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Get My Public IP Address

get stdout to variable and stdout at sametime
Sometimes you want to write the script output to stdout but you need to send it to email. If you use: $ var="$( ls / )"; $ echo -e "$var"; works but, you need to wait the script terminate to bufferize then print the output var; With this way, you can use/work/print the output before the variable receive all the output content, then after it you can use the variable for anything else, like send email.

shutdown pc in 4 hours without needing to keep terminal open / user logged in.
From the 'disown' man page: disown prevents the current shell from sending a HUP signal to each of the given jobs when the current shell terminates a login session.

Detach a process from the current shell
ignore HUP interruptions

Given $PID, print all child processes on stdout
Simpler.

Fetch the current human population of Earth
They are using json now

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" }

send tweets to twitter (and get user details)
great for outputting tweets from cron jobs and batch scripts

Find distro name and/or version/release
Works for most distributions, tested on Ubuntu, Fedora, CentOS, Gentoo, SUSE, RedHat. Debian and Slackware: $cat /etc/*version

Use a decoy while scanning ports to avoid getting caught by the sys admin :9
Scan for open ports on the target device/computer (192.168.0.10) while setting up a decoy address (192.168.0.2). This will show the decoy ip address instead of your ip in targets security logs. Decoy address needs to be alive. Check the targets security log at /var/log/secure to make sure it worked.


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