realpath

real_path () {
    TARGET_FILE=$1
    cd `dirname $TARGET_FILE`
    TARGET_FILE=`basename $TARGET_FILE`

    # Iterate down a (possible) chain of symlinks
    while [ -L "$TARGET_FILE" ]
    do
        TARGET_FILE=`readlink $TARGET_FILE`
        cd `dirname $TARGET_FILE`
        TARGET_FILE=`basename $TARGET_FILE`
    done

    # Compute the canonicalized name by finding the physical path
    # for the directory we're in and appending the target file.
    PHYS_DIR=`pwd -P`
    RESULT=$PHYS_DIR/$TARGET_FILE
    echo $RESULT
}