How to password protect a pdf file on mac?

Yes, podofoencrypt is a valid and completely free method to password protect a PDF on Mac, provided you're comfortable using the command line. It is one of the tools included in the open-source PoDoFo library, which is available for macOS.

First, you'll need to install the PoDoFo tools. The easiest way is via Homebrew:

1. Open the Terminal app.

2. Run the following command: brew install podofo.

Once installed, you can use the following command structure to password protect a PDF on Mac:

bash

podofoencrypt -u "USER_PASSWORD" -o "OWNER_PASSWORD" input.pdf output.pdf

• -u "USER_PASSWORD": The password required to open the PDF. Replace this with your chosen password.
• -o "OWNER_PASSWORD": The password required to change permissions (like printing or copying). This is a required argument.
• input.pdf: The path to your original PDF file.
• output.pdf: The name and path for your new, password-protected PDF.

podofoencrypt also allows you to control what users with the "user password" can do with the document. You can add permission flags to the command to restrict actions:

• --print: Allow printing the document.
• --copy: Allow extraction of text and graphics.
• --edit: Allow modification of the document.
• --fillandsign: Allow filling in forms and adding signatures.

For example, to create a PDF that can be opened with user123 but cannot be printed, you would run:

bash

podofoencrypt -u "user123" -o "owner456" --print input.pdf output.pdf

Note: The --print flag is used to allow printing. If you omit it, printing is disallowed.