Shell Script to Bulk Delete Notes from PowerPoint for Mac

Introduction

PowerPoint presentation files (*.pptx) allow you to add notes to each slide. However, PowerPoint for Mac does not have a built-in feature to bulk delete these notes. This article automates note deletion using a shell script.

Shell Script Explanation

This shell script (delete_note.sh) performs the following operations:

1. Creates a temporary directory and stores its path in the TMP_DIR variable.

2. For each pptx file in the current directory, it performs the following:

   1. Copies the .pptx file to the temporary directory.
   2. Extracts the .pptx file in the temporary directory.
   3. For each .xml file in the ./ppt/notesSlides/ directory, clears the content of <a:t> tags.
   4. Re-archives the extracted files into a .pptx file.
   5. Copies the generated .pptx file back to the original directory.

3. Deletes the temporary directory.

Shell Script

#!/bin/bash

set -eu

TMP_DIR="$(mktemp -d)"
trap 'rm -rf $TMP_DIR' EXIT

for PPTX_FILE in *.pptx; do
    if [ -e "$PPTX_FILE" ]; then
        echo "Processing $PPTX_FILE..."

        cp "$PPTX_FILE" "$TMP_DIR"
        pushd "$TMP_DIR"

        unzip "$PPTX_FILE"
        rm "$PPTX_FILE"
        find "./ppt/notesSlides/"*.xml | xargs -I{} sed -i '' -e 's/<a:t>[^<]*<\/a:t>/<a:t><\/a:t>/g' "{}"
        zip -0 -r "$PPTX_FILE" ./* # do not compress (-0)

        popd

        cp "$TMP_DIR/$PPTX_FILE" "$PPTX_FILE"
    fi
done

Background: PPTX File Structure

A PPTX file is actually a collection of XML files. Specifically, it has the following structure:

• _rels/: Directory containing XML files that define relationships.
• docProps/: Directory containing XML files that define document properties.
• pptx Directory containing XML files that make up the presentation body.
  • slides/: Directory containing XML files with information for each slide.
  • slideMasters/: Directory containing XML files with slide master information.
  • notesMasters/: Directory containing XML files with notes master information.
  • notesSlides/: Directory containing XML files with notes information for each slide.
  • theme/: Directory containing XML files with theme information.
• _rels/: Directory containing XML files that define relationships.
• [Content_Types].xml: XML file that defines content types.

These XML files are compressed into a PPTX file. In other words, to edit a PPTX file, you need to extract it, modify the XML files, and re-compress it. Not knowing this structure can leave you stuck when managing PowerPoint for Mac.