Commands by karld (3)

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Ask for a password, the passwd-style
You can ask repeatedly for a non-blank password using this function: function read_password() { while [ ! -n "$USER_PASSWORD" ]; do read -s -p"Password: " USER_PASSWORD if [ ! -n "$USER_PASSWORD" ]; then echo "ERROR: You must specify a valid password, please try again" fi echo done } Also you can set a time out (in seconds) to write the password read -t 10 -s -p"Password: " USER_PASSWORD_VARIABLE if [ ! $? -eq 0 ]; then echo "Time out!" fi

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" }

Fix borked character coding in a tty.
Often you find some tty programs are messed up and confused about character encoding - 'man' is a common problem and sometimes displays weird characters for apostrophes, hyphens etc etc. Another class of programs that suffer from this are those that try to use the line drawing characters - eg RedHat's tty system admin functions such as system-config-firewall-tui system-config-network-tui etc. Adding 'LC_ALL=C' fixes most of these problems (as long as you want English! Perhaps speakers of other languages can add a comment here). For bonus points, I've added the '-c' option to the man command so that it ignores it's cache and re-computes the man page using the C locale.

Show a Package Version on RPM based distributions
if you want to see all information about a package use: rpm -qi pkgname full list of querytags can be accessed by the command: rpm --querytags you can also customize the query format how ever you like with using more querytags together along with escape sequences in "man printf"! you can also use more than one package name. for example this command shows name and version in to columns: rpm -q --queryformat %-30{NAME}%{VERSION}\\n pkg1 pkg2

Are the two lines anagrams?
This is just a slight alternative that wraps all of #7917 in a function that can be executed

Compute the average number of KB per file for each dir
Shorter version using --tag

Burn CD/DVD from an iso, eject disc when finished.
cdrecord -scanbus will tell you the (x,y,z) value of your cdr (for example, mine is 3,0,0)

open path with your default GNOME program
Another step to bring cli and gui closer together: gnome-open It opens a path with the default (gui) application for its mime type. I would recommend a shorter alias like alias o=gnome-open More examples: $ gnome-open . [opens the current folder in nautilus / your default file browser] $ gnome-open some.pdf [opens some.pdf in evince / your default pdf viewer] $ gnome-open trash:// [opens the trash with nautilus] $ gnome-open http://www.commandlinefu.com [opens commandlinefu in your default webbrowser]

Get IP from hostname
Get the IP of a hostname.

Viewable terminal session over network.
connect to it with any network command (including web browser - if you don't mind weird formatting) curl 127.0.0.1:9876 nc 127.0.0.1 9876


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