Commands by chars19 (2)

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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" }

Blue Matrix
Same as original, but works in bash

Count the frequency of every word for a given file
Counts the frequency of words in a file

View ~/.ssh/known_hosts key information
Will return the SSH server key information for each host you have in your ~/.ssh/known_hosts file, including key size, key fingerprint, key IP address or domain name, and key type.

Cleanly manage tempfiles in scripts
Cleanly create tempfiles using mktemp and remove them using traps instead of removing them in the end of the script. This way, you make sure the tempfiles are removed properly even if the script is killed or interrupted. For a user script in KDE4, you can set TMPROOT using : $ TMPROOT=$(kde4-config --path tmp)

Capitalize first letter of each word in a string - A ruby alternative
"-n" loops around ; "-e" executes the given quoted string ; "$_" is the current line ; "split" creates an array on white space; each item of the array is "collected" to be then "capitalized" ; the array is "joined" back into a string.

Test load balancers
With the "--resolve" switch, you can avoid doing DNS lookups or edit the /etc/hosts file, by providing the IP address for a domain directly. Useful if you have many servers with different IP addresses behind a load balancer. Of course, you would loop it: $ for IP in 10.11.0.{1..10}; do curl --resolve subdomain.example.com:80:$IP subdomain.example.com -I -s; done

Make a ready-only filesystem ?writeable? by unionfs
First look into /etc/modules if you have unionfs (or squashfs) support. If not, add the modules. UnionFS combines two filesystems. If there is a need to write a file, /tmp/unioncache will be used to write files (first create that directory). Reads will be done where the file is found first. http://tldp.org/HOWTO/SquashFS-HOWTO/creatingandusing.html

Search google and show only urls
Get the first 10 google results form a querry, but showing only the urls from the results. Use + to search diferent terms, ex: commandlinefu+google .

Backup file, create dir and set perms in one shot
Prior to working on/modifying a file, use the 'install -m' command which can both copy files, create directories, and set their permissions at the same time. Useful when you are working in the public_html folder and need to keep the cp'd file hidden.

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