Commands by swormley (1)

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cd to (or operate on) a file across parallel directories
This is useful for quickly jumping around branches in a file system, or operating on a parellel file. This is tested in bash. cd to (substitute in PWD, a for b) where PWD is the bash environmental variable for the "working directory"

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" }

Create incremental snapshots of individual folders using find and tar-gzip
Creates an incremental snapshot of individual folders.

set prompt and terminal title to display hostname, user ID and pwd
used in an if-then-else in case the default shell is ksh, not bash. The $(basename ${0#-}) is handy to echo which shell and strip the dash some flavors put in front of "bash" if [ $(basename ${0#-}) == "bash" ] ; then export PS1='\[\e]0;\h \u \w\a\]\n\[\e[0;34m\]\[email protected]\h \[\e[33m\]\w\[\e[0;32m\]\n\$ ' else HOST=`hostname` ESC=`echo "\033"` BEL=`echo "\007"` RAW=`echo "\r"` export PS1='-${RAW}${ESC}]0;${HOST} ${USER}${BEL}-${ESC}[0;34m${USER}${ESC}[[email protected]${ESC}[0;34m${HOST%%.*}${ESC}[0;33m${ESC}[0m $ ' fi

Get all these commands in a text file with description.
I tried out on my Mac, jot to generate sequence ( 0,25,50,..), you can use 'seq' if it is linux to generate numbers, need curl installed on the machine, then it rocks. @Satya

Find the package that installed a command

setup a tunnel from destination machine port 80 to localhost 2001, via a second (hub) machine.
this is handy when the hubmachine is the only machine that can connect to the destination machine (allowed on ip by firewall) and you want to access it from your laptop.

List of commands you use most often
Plot your most used commands with gnuplot.

get all Google ipv4 subnets for a iptables firewall for example
a bit shorter, parenthesis not needed but added for clarity

Find file containing namespace in a directory of jar files.
You could subsitute javax.servlet for any namespace you need.


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