How to check if a directory exists in a shell script

To check if a directory exists in a shell script you can use the following:

    if [ -d "$DIRECTORY" ]; then    # Control will enter here if $DIRECTORY exists.  fi

Or to check if a directory doesn't exist:

    if [ ! -d "$DIRECTORY" ]; then    

        # Control will enter here if $DIRECTORY doesn't exist.  

    fi

---

subsequent commands may not work as intended if you do not take into account that a symbolic link to a directory will also pass this check. E.g. running this:

    ln -s "$ACTUAL_DIR" "$SYMLINK"  

    if [ -d "$SYMLINK" ]; then     

        rmdir "$SYMLINK"   

    fi

Will produce the error message:

    rmdir: failed to remove `symlink': Not a directory

So symbolic links may have to be treated differently, if subsequent commands expect directories:

    if [ -d "$LINK_OR_DIR" ]; then     

    if [ -L "$LINK_OR_DIR" ]; then      

        # It is a symlink!      

        # Symbolic link specific commands go here.      

        rm "$LINK_OR_DIR"    

    else      

        # It's a directory!      

        # Directory command goes here.      

        rmdir "$LINK_OR_DIR"    

    fi  

    fi