Commands by tobiasboon (5)

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Update a namecheap @ A record to point to your current internet-facing IP address
Sets the @ A record for your domain hosted by namecheap to your current internet-facing IP address, logs success or failure with syslog, and logs the data returned to /root/dnsupdate. Change the XXX's as appropriate. More info at: http://www.namecheap.com/support/knowledgebase/article.aspx/29/

Find files and calculate size of result in shell
Using find's internal stat to get the file size is about 50 times faster than using -exec stat.

Inverted cowsay
It's quite fun to invert text using "flip.pl" (ref: http://ubuntuforums.org/showthread.php?t=2078323 ). Slightly more challenging is to flip a whole "cowsay". :-)

Make a zip file with date/time created in the name of the file , zip all sub-directorys
zip -r /tmp/filename-`date +%Y%m%d_%H%M%S`.zip /directory/

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'"

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"

Backup trought SSH

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"

quick integer CPU benchmark
This is a quick and dirty way to generate a (non-floating-point) CPU-bound task to benchmark. Adjust "20" to higher or lower values, as needed. As a benchmark this is probably a little less bogus than bogomips, and it will run anywhere 'bc' does.

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" }


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