OS X Mail - 在撰写模式下打开 *.eml 文件

Question

How can I open *.eml-files in compose mode for Mac OS X Mail? For Outlook "X-Unsent: 1" seems to do the trick, but does not work for Mac OS X Mail still opens in Read-Only.

Answer 1

This is a super old question, but obviously has received a fair number of views. My curiosity piqued, I figured I'd take a look. After some fiddling around, I found you can add the following header to make a message editable:

X-Uniform-Type-Identifier: com.apple.mail-draft

Add that to your otherwise RFC-2822 compliant message, give it a .eml or .emlx extension, and when you double-click it'll open as an editable message in Mail.app.

Have fun.

Answer 2

In macOS Catalina 10.15.7, running the following commands from a Python script worked to open a new message and then switch to compose mode, but there is a race condition between opening the message and putting it in Compose mode if the osascript command runs too quickly. The sleep command is there to prevent the race, but you may need to adjust the length of sleep time to compensate for this. (I also used time.sleep(1) in Python instead of the shell command.)

/usr/bin/open -a Mail path/to/tmp/message.eml
/bin/sleep 1
/usr/bin/osascript -e 'tell application "System Events" to tell application process "Mail"' -e 'keystroke "d" using {command down, shift down}' -e 'end tell'

Note that you must grant access to Terminal to control other apps, or the osascript command will fail with an error. To do that, open System Preferences, click on the Security & Privacy item, click Accessibility from the left menu, click the lock icon to unlock the menu, then check the Terminal item (or add it if not listed) in the "Allow apps to control your computer." list.

Also note that the Cmd-Shift-D keyboard shortcut sends a message that is already in compose mode, so if someone is using Mail at the time the script runs, and they have a separate compose window in the foreground, then the script could send that message instead of putting the new message in compose mode.