cd cd . cd .. cd /tmp cd /tmp/testdir cd /tmp/testdir/ cd /tmp cd testdir cd /tmp/testdir/. dir cd dir /tmp/testdir/ echo "hello world" echo helloworld set abc = helloworld echo $abc set def = testdir cd /tmp/$def/ set ghi = tmp dir /$ghi/$def set jkl = outdir dir /$ghi/$def > $jkl echo outdir echo $jkl prog1 100 200 set ghi = 100 prog1 $ghi 200 prog2 100 200 < input.txt > output.txt set abc = output prog2 100 200 < input.txt > $abc.txt echo "hello world" >> $abc.txt echo helloworld >> $abc.txt