Commands by treebeard (1)

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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" }

100% rollback files to a specific revision

display a one-liner of current nagios exit statuses. great with netcat/irccat

Find the top 10 directories containing the highest number of files
It can be used to pinpoint the path(s) where the largest number of files resides when running out of free i-nodes

list block devices
Shows all block devices in a tree with descruptions of what they are.

LIST FILENAMES OF FILES CREATED TODAY IN CURRENT DIRECTORY
Then pipe to 'xargs ls' for a familiar listing, possibly using find's -print0 and xarg's -0 options.

Backup a file with a date-time stamp
Appends the input file with the date format YYYY-MM-DD.bak. Also runs silently if you remove the -v on the cp at the end of the function.

Set laptop display brightness
Run as root. Path may vary depending on laptop model and video card (this was tested on an Acer laptop with ATI HD3200 video). $ cat /proc/acpi/video/VGA/LCD/brightness to discover the possible values for your display.

Benchmark SQL Query
Benchmark a SQL query against MySQL Server. The example runs the query 10 times, and you get the average runtime in the output. To ensure that the query does not get cached, use `RESET QUERY CACHE;` on top in the query file.

LIST FILENAMES OF FILES CREATED TODAY IN CURRENT DIRECTORY
This version eliminates the grep before the awk, which is always good. It works for GNU core utils and ensures that the date output of ls matches the format in the pattern match, regardless of locale, etc. On BSD-based systems, you can easily eliminate both the grep and the awk: find . -maxdepth 1 -Btime -$(date +%kh%lm) -type f


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