Since I'm bouncing between OSX and Linux a lot, I have a shell script with the same name on each that boils down to:
if [ `uname` == "Darwin" ]; then
pbcopy
else
xsel --clipboard
fi
why not just alias?
Could be an alias, I have a limited set of aliases for each type of system. But I keep a repository of hundreds of personal shell scripts and it fit better there.