Commands using uniq (255)

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Insert the last argument of the previous command
for example if you did a: $ ls -la /bin/ls then $ ls !$ is equivalent to doing a $ ls /bin/ls

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.

Detect illegal access to kernel space, potentially useful for Meltdown detection
Based on capsule8 agent examples, not rigorously tested

camelcase to underscore
Convert a camelCase string into snake_case. To complement senorpedro's command.

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" }

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" }

Update all Docker Images

Find all active ip's in a subnet

Application network trace based on application name
This command takes an application name as an argument and then it will listen to the tcp traffic and capture packets matching the process Id of the application. The output shows: local address / local port / Remote Address / Remote port / State / Owning Process ID

Print text string vertically, one character per line.
Define a function $ vert () { echo $1 | grep -o '.'; } Use it to print some column headers $ paste

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