Commands using cat (511)

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diff two unsorted files without creating temporary files
bash/ksh subshell redirection (as file descriptors) used as input to diff

Find usb device in realtime
Using this command you can track a moment when usb device was attached.

Create a temporary file
To create directory, use: $ tempdir=$(/bin/mktemp -d)

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" }

enumerate with padding
bash2 : for X in $(seq 1 5); do printf "%03g " "$X";done bash3 : for X in {1..5}; do printf "%03g " "$X";done bash4 : echo {001..5}

convert strings toupper/tolower with tr

Install pip with Proxy
Installs pip packages defining a proxy

online MAC address lookup

Substrings a variable
substrings a variable starting at position. If no offset given prints rest of the line

Find usb device in realtime
Using this command you can track a moment when usb device was attached.


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