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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\[\e[0;34m\]\u@\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}${ESC}[0m@${ESC}[0;34m${HOST%%.*}${ESC}[0;33m${ESC}[0m $ ' fi

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 all MySQL Databases to individual files
No need to loop when we have `xargs`. The sed command filters out the first line of `show databases` output, which is always "Database".

Signals list by NUMBER and NAME

Top 15 processes with the largest number of open files
See the summary.

For finding out if something is listening on a port and if so what the daemon is.

Last month
Work out last months value

Buffer in order to avoir mistakes with redirections that empty your files
A common mistake in Bash is to write command-line where there's command a reading a file and whose result is redirected to that file. It can be easily avoided because of : 1) warnings "-bash: file.txt: cannot overwrite existing file" 2) options (often "-i") that let the command directly modify the file but I like to have that small function that does the trick by waiting for the first command to end before trying to write into the file. Lots of things could probably done in a better way, if you know one...

Tweet from Terminal to twitter !
Tweeting from terminal to twitter accounts..

Print process run time, average CPU usage, and maximum memory usage on exit
Bash has a built-in time command which provides less functionality than the real time command. Thus we reference /usr/bin/time directly. Since the command isn't very easy to remember you could alias it to something like "cputime" or even just "time".


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