Commands by sitaram (5)

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Exclude multiple columns using AWK
Print all columns except the 1st and 3rd.

Perl One Liner to Generate a Random IP Address

Makes the permissions of file2 the same as file1
Also works with: $chgrp --reference file1 file2 $chown --reference file1 file2

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"

Show apps that use internet connection at the moment.
show only the name of the apps that are using internet

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" }

remove all spaces from all files in current folder

prevents replace an existing file by mistake
Use set +o noclobber and you will be able to replace files again

List the binaries installed by a Debian package
GNU grep's perl-compatible regular expression(PCRE).

Display or use a random file from current directory via a small bash one-liner
An other way to run it ( playing a random file ending with avi, flv or mpeg ) from a specified dir and a specified type of extension : making MOVIE array with a glob : $ MOVIE=( /PATH/TO/MY/FAVORITE/MOVIES/*.{avi,flv,mpeg} ) playing the random file from a random key from the array $ mplayer ${MOVIE[ RANDOM % ( ${#i[@]} + 1 ) ]]} I use only globs and a bash array. I use GNU bash, version 3.2.48


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