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Rename files in batch

Create a bunch of dummy text files
Using the 'time' command, running this with 'tr' took 28 seconds (and change) each time but using base64 only took 8 seconds (and change). If the file doesn't have to be viewable, pulling straight from urandom with head only took 6 seconds (and change)

display ip address
add this alias in .bashrc to fast check the ip address of your modem router alias myip="curl -s http://myip.dk | grep '' | sed -e 's/]*>//g'"

check open ports without netstat or lsof

Join lines
awk version of 7210. Slightly longer, but expanding it to catch blank lines is easier: $ awk 'BEGIN{RS="\0"}{gsub(/\n+/,"");print}' file.txt

Get a regular updated list of zombies
to omit "grep -v", put some brackets around a single character

Output Windows services in a neatly formated list (cygwin)
Outputs Windows Services service name and display name using "sc query", pipes the output to "awk" for processing, then "column" for formatting. List All Services: $ sc query state= all | awk '/SERVICE_NAME/{printf"%s:",$2;getline;gsub(/DISP.*:\ /,"");printf"%s\n",$0}' | column -ts\: List Started Services: $sc query | awk '/SERVICE_NAME/{printf"%s:",$2;getline;gsub(/DISP.*:\ /,"");printf"%s\n",$0}' | column -ts\: List Stopped Services: $sc query state= inactive| awk '/SERVICE_NAME/{printf"%s:",$2;getline;gsub(/DISP.*:\ /,"");printf"%s\n",$0}' | column -ts\:

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" }

Count Files in a Directory with Wildcards.
Remove the '-maxdepth 1' option if you want to count in directories as well

Display IPs accessing your Apache webserver.


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