bash example

for x in one two three four
do
    echo number $x
done

for myfile in /etc/r*
do
    if [ -d "$myfile" ]
    then
      echo "$myfile (dir)"
    else
      echo "$myfile"
    fi
done

for x in /etc/r??? /var/lo* /home/drobbins/mystuff/* /tmp/${MYPATH}/*
do
    cp $x /mnt/mydir
done

while [ condition ]
do
    statements
done

myvar=0
until [ $myvar -eq 10 ]
do
    echo $myvar
    myvar=$(( $myvar + 1 ))
done

case "${x##*.}" in
     gz)
           gzunpack ${SROOT}/${x}
           ;;
     bz2)
           bz2unpack ${SROOT}/${x}
           ;;
     *)
           echo "Archive format not recognized."
           exit
           ;;
esac   

Functions

tarview() {
    echo -n "Displaying contents of $1 "
    if [ ${1##*.} = tar ]
    then
        echo "(uncompressed tar)"
        tar tvf $1
    elif [ ${1##*.} = gz ]
    then
        echo "(gzip-compressed tar)"
        tar tzvf $1
    elif [ ${1##*.} = bz2 ]
    then
        echo "(bzip2-compressed tar)"
        cat $1 | bzip2 -d | tar tvf -
    fi
}

myvar="hello"

myfunc() {
    local x
    local myvar="one two three"
    for x in $myvar
    do
        echo $x
    done
}

myfunc

echo $myvar $x