Commands using sysctl (10)

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convert plain .avi movies to .mpeg
works "out of the box" on ubuntu 8.10

flip faster and more precisely through commands saved in history
flip shell history with PG UP/PG DOWN like with arrows. just type ss and PG UP and see all ssh commands, type ls and PG DOWN - see all ls commands. need to uncomment two options in /etc/inputrc: "\e[5~": history-search-backward "\e[6~": history-search-forward hack found: http://broddlit.wordpress.com/2008/04/12/making-the-bash-history-a-better-place/

Display the top ten running processes - sorted by memory usage
ps returns all running processes which are then sorted by the 4th field in numerical order and the top 10 are sent to STDOUT.

Console clock
A console clock with the current time.

Working random fact generator
Though without infinite time and knowledge of how the site will be designed in the future this may stop working, it still will serve as a simple straight forward starting point. This uses the observation that the only item marked as strong on the page is the single logical line that includes the italicized fact. If future revisions of the page show failure, or intermittent failure, one may simply alter the above to read. $ wget randomfunfacts.com -O - 2>/dev/null | tee lastfact | grep \ | sed "s;^.*\(.*\).*$;\1;" The file lastfact, can then be examined whenever the command fails.

livehttpheaders (firefox addon) replacement
Default output-file is "liveh.txt". This uses only BRE, in case you're using an older version of sed(1) that doesn't have support for ERE added. With a modern sed(1), to reduce false positive matches, you might do something like: liveh(){ tcpdump -lnnAs512 -i ${1-} tcp |sed 's/.*GET /GET /;s/.*Host: /Host: /;s/.*POST /POST /;/GET |Host: |POST /!d;/[\"'"'"]/d;/\.\./d;w '"${2-liveh.txt}"'' >/dev/null ;} Anyway, it's easy to clean up the output file with sed(1) later.

Re-read partition table on specified device without rebooting system (here /dev/sda).

Display the number of connections to a MySQL Database
Count the number of active connections to a MySQL database. The MySQL command "show processlist" gives a list of all the active clients. However, by using the processlist table, in the information_schema database, we can sort and count the results within MySQL.

Share a screen session

Display a markdown file in a new tab in firefox


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