Commands by digitalmechanic (2)

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Decode base64-encoded file in one line of Perl
Another option is openssl.

check open ports without netstat or lsof

Get all mac address
I prefer the ip command to ifconfig as ifconfig is supposedly going to be deprecated. Certain IP address aliases can only be seen with the ip command (such as the ones applied by RHCS).

scan whole internet and specific port in humanistic time
apt-get install git gcc make libpcap-dev git clone https://github.com/robertdavidgraham/masscan cd masscan make install -pDm755 bin/masscan /usr/bin/masscan

Console clock
Shows a simple clock in the console -t param removes the watch header Ctrl-c to exit

Convert CSV to JSON
Replace 'csv_file.csv' with your filename.

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" }

List only directories, one per line

Remove lines that contain a specific pattern($1) from file($2).
The -i option in sed allows in-place editing of the input file. Replace myexpression with any regular expression. /expr/d syntax means if the expression matches then delete the line. You can reverse the functionality to keep matching lines only by using: $ sed -i -n '/myexpression/p' /path/to/file.txt

Add "prefix" on a buch of files


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