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Find a file's package or list a package's contents.
This is the fastest method to search the Debian package database. Requires the dlocate package. The dlocate db updates periodically, but you may force an update with # dlocate-update

Get the time from NIST.GOV
The format is JJJJJ YR-MO-DA HH:MM:SS TT L DUT1 msADV UTC(NIST) OTM and is explained more fully here: http://tf.nist.gov/service/acts.htm

Set all CPU cores' CPU frequency scaling governor to maximum performance

Content search.
Grep will read the contents of each file in PWD and will use the REs $1 $2 ... $n to match the contents. In case of match, grep will print the appropriate file, line number and the matching line. It's just easier to write $ ff word1 word2 word3 Instead of $ grep -rinE 'word1|word2|word3' .

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"

What is My WAN IP?
The curl command retrieve the HTML text containing the IP address. The grep command picks out the IP address from that HTML text.

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"

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" }

Write comments to your history.
A null operation with the name 'comment', allowing comments to be written to HISTFILE. Prepending '#' to a command will *not* write the command to the history file, although it will be available for the current session, thus '#' is not useful for keeping track of comments past the current session.

Google text-to-speech in mp3 format
Usage: t2s 'How are you?' Nice because it automatically names the mp3 file up to 15 characters Modified (uses bash manip instead of tr) t2s() { wget -q -U Mozilla -O $(cut -b 1-15


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