kill all processes by path name

To kill all processes whose executable lies in a certain path issue the following command under Linux:

ps xawww -o pid -o cmd | \
egrep /path/to/executable | \
egrep -o ^[[:digit:]]+ | \
xargs kill

And for Mac OS X:

ps xwww -o pid -o comm | \
egrep /path/to/executable | \
egrep -o ^[[:digit:]]+ | \
xargs kill

loopkid