Commands by linuts (7)

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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" }

Convert CSV to JSON
Replace 'csv_file.csv' with your filename.

give a binary the ability to open ports below 1024 as non root user
Binding a server to privileged port on Linux w/o running as root This is applicable to any service using privileged ports (< 1024), for instance to run a HTTP server on port 80 or a LDAP directory server on port 389 for example.

Find out when your billion-second anniversary is (was).
This is the same command as this one, but for OS X. http://www.commandlinefu.com/commands/view/3053/find-out-when-your-billion-second-anniversary-is-was.

static compilation

Install Linux Kernel Headers

Secure netcat chat - SSH
client: $ nc localhost 9876

Enable cd by variable names
Usage: $ mydir=/very/long/path/to/a/dir $ cd mydir I often need to cd where no man wants to go (i.e. long path). by enabling the shell option cdable_vars, I can tell cd to assume the destination is the name of a variable.

Block all FaceBook traffic

Get your local IP regardless of your network interface
Shows only IP-addresses of ifconfig except 127.0.0.0/8. I fixed the script to work on more systems and configs short info /inet/!d; #grep inet /127.0/d; # grep -v 127.0 /dr:\s/d; # grep -v dr: s/^.*:\(.*\)B.*$/\1/ # remove everything exept between : and B


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