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List only the directories
This command would be useful when it is desirable to list only the directories. 'egrep' chooses only the lines that begin with 'd'.

which procs have $PATH_REGEX open?
faster than lsof by at least x2 on my box.

Create a new file

Convert a date to timestamp
Simple way to get a timestamp from a date

Show the PATH, one directory per line
This is useful for examining the path.

Forget remembered path locations of previously ran commands
i.e.: Useful if you add ~/bin to your $PATH and you want to override locations of previously ran commands and you don't want to log out and log back in to be able to use them.

Lets Tux say the random fact. [add it to .bashrc to see it in new terminal window]

Uniquely (sort of) color text so you can see changes
Colorify colors input by converting the text to a number and then performing modulo 7 on it. This resulting number is used as the color escape code. This can be used to color the results of commands with complex outputs (like "482279054165371") so if any of the digits change, there's a good chance the color will change too. I say good chance because there's only 7 unique colors here, so assuming you were watching random numbers, there would be a 6/7 chance that the color would change when the number changed. This should really only be used to help quickly identify when things change, but should not be the only thing relied upon to positively assert that an output has not changed.

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" }

Multi line grep using sed and specifying open/close tags
Working with log files that contains variable length messages wrapped between open and close tags it may be useful to filter the messages upon a keyword. This works fine with GNU sed version 4.2 or higher, so pay attention to some unix distros (solaris, hp-ux, etc.). Linux should be ok.


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