Commands by mesuutt (9)

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Print a row of 50 hyphens
Get there by going backwards and forgetting the numbers.

Produce a pseudo random password with given length in base 64
Don't copy trailing '=' or use head -c to limit to desired length.

Single use vnc-over-ssh connection
This command 1. SSH into a machine 2. Tunnels VNC port to your local computer ("-L 5900:localhost:5900") 3. Runs a single use vnc server ("x11vnc -safer -localhost -nopw -once -display :0") 4. Goes into the background ("-f") 5. Runs VNC viewer on the local computer connecting to the remote machine via the newly created SSH tunnel ("vinagre localhost:5900")

return a titlecased version of the string[str.title() in python]

watch iptables counters
Watch the number of packets/bytes coming through the firewall. Useful in setting up new iptables rules or chains. Use this output to reorder rules for efficiency.

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" }

most used commands in history (comprehensive)
Most of the "most used commands" approaches does not consider pipes and other complexities. This approach considers pipes, process substitution by backticks or $() and multiple commands separated by ; Perl regular expression breaks up each line using | or < ( or ; or ` or $( and picks the first word (excluding "do" in case of for loops) note: if you are using lots of perl one-liners, the perl commands will be counted as well in this approach, since semicolon is used as a separator

regex for turning a URL into a real hyperlink (i.e. for posting somewhere that accepts basic html)
This should work with anything://url.whatever etc etc ;)

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"

Calculate days on which Friday the 13th occurs (inspired from the work of the user justsomeguy)
Friday is the 5th day of the week, monday is the 1st. Output may be affected by locale.


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