Secret Cache of WeChat

By chance, yesterday when I clicked on a message with a link to a document file in Mac's WeChat app, I was prompt to Finder. To my surprice, this is a deep and secret space where WeChat stores temporary files.

Further exploration, I found its path from file info in Finder.

From there I copied the full path from Where. Here is the full path

/Users/xxx/Library/Containers/com.tencent.xinWeChat/Data/Library/Application Support/com.tencent.xinWeChat/2.0b4.0.9/f5210b300b4abef170762c8c1ddf67c5/Message/MessageTemp/2d14efe546045554426bdf707c13cead

I understand that WeChat saves some information such as images, files, videos in local cache so that there would be no need to download those information again for displaying (and much qicker) when user clicks on thos items. However, I don't know where they are and how long those items are stored, forever?

From this sneak, I could go up to other folders to see what items are saved. There are quite a lots of items in this library cache. I guess that those items would be purgeble items in system cache.

I got Mac mini M1

I just got Mac mini M1 2020 model, refurblished one. I have been kept watching Mac mini M1 for long time. The Mac mini box is very small, powerful, and attactive Mac computer. In addition to that, the cost is another reason, much less that iMac or macBook air or pro. This model saves me CAD$170.

This is my first expirence with Mac mini. Basically, it is just computer box with powerful CPU & GPU, internal speaker and several ports for peripheral connection. To make it work in a way as same as iMac, for example, a monitor, a keyboard, mouse or trackpad are needed as minimal.

In addtion to the minimal, for my case, I purchased a web camera for facetime or web conference. I have an external speaker with better sound quality. The Mac mini box does not have any internal microphone, but I found that web camera's microphone is good enough. There are 2 USB ports in the mini box. I need more ports for my keyboard, mouse, web camera, extrenal HD as time machine, and printer. Therefore, I need two USB hubs (4 USB ports for one hub) for more connections.

For my experienment, I tried to use USB port to connect the Mac mini to my existing iMac 21, using iMac screen as monitor. I thought that if I could see Mac mini HD, I would be able to boot from it through System Preferences' boot disk setting. Unfortunately, I cannot see Mac mini HD from my iMac. Finally I realize that it makes sense. The HD within Mac mini box is not in the same way as external HD to USB port. Any way, it is a good try. Currently I have an old monitor for use. The new one, Samsung 24" FHD 75Hz 5ms GTG IPS LED FreeSync Gaming Monitor (LF24T350FHNXZA), is on the way shipping to my house.

References

• Apple Certifiled Refurbished (Canada): Guaranteed Apple quality

Add Picture to PDF File

Preview is a versatile tool to view and edit various types of files, including PDF. For example, by using Preview, you can add new text, lines, object shapes to a PDF file. However, it seems, at first,  that images could not be directly added to PDF file(no ways from Previews' menu or toolbar icons), none be directly pasted to.

Just a shorting time searching from internet, I found a way to do that.  Here is the trick to do that:

1. First copy and paste an image to Preview by Ctrl+N as a new image file;
2. then select all or part of image and make a copy (Ctrl+C).
3. Paste the selection by Ctrl+V.
4. Select all again (Ctrl+A), and
5. cut the selection(Ctrl+X). This new copy will be as an object instead of image.
6. The last step is to paste the object to your PDF file in Preview by Ctrl+V!

References

• How-To Geek article: Hwo to Add An Image a PDF File with Preview