Commands by taintedkernel (5)

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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" }

processes per user counter
enumerates the number of processes for each user. ps BSD format is used here , for standard Unix format use : ps -eLf |awk '{$1} {++P[$1]} END {for(a in P) if (a !="UID") print a,P[a]}'

search for files or directories, then show a sorted list of just the unique directories where the matches occur
Ever use 'locate' to find a common phrase in a filename or directory name? Often you'll get a huge list of matches, many of which are redundant, and typically the results are not sorted. This command will 'locate' your search phrase, then show you a sorted list of just the relevant directories, with no duplications. So, for example, maybe you have installed several versions of the java jre and you want to track down every directory where files matching "java" might exist. Well, a 'locate java' is likely to return a huge list with many repeated directories since many files in one directory could contain the phrase "java". This command will whittle down the results to a minimal list of unique directory names where your search phrase finds a match.

Convert mysql database from latin1 to utf8
MySQL: CHARSET from latin1 to utf8

Watch RX/TX rate of an interface in kb/s
Just a simple way without the need of additional tools. Of course, replace eth0 with your IF.

files and directories in the last 1 hour
added alias in ~/.bashrc alias lf='find ./* -ctime -1 | xargs ls -ltr --color'

Simple MAC Changeing
The 00:11:22:33:44:55 is whatever you want your new MAC address to be. Sometimes sudo should be used in front if you need to.

find out how many days since given date
You can also do this for seconds, minutes, hours, etc... Can't use dates before the epoch, though.

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" }

tcpdump top 10 talkers
capture 2000 packets and print the top 10 talkers


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