Airdroid, Ubuntu, and Permissions
Gary Schafer, 23 December 2013
I am currently running Ubuntu 12.04 LTS (long term support). I also have a Samsung Galaxy S2 plus a Samsung / Google Nexus 10. Unfortunately, when Android updated their OSes to the latest kernel, they no longer supported PTP for file transfer; they only supported MTP. Linux took a bit to catch up. In the meantime, there was a nice, small app I could load onto each of these devices called Airdroid. Airdroid allows a user to essentially remote in to their device. I primarily used it to transfer files from my phone and tablet to my computer.
Unfortunately, there was an update done recently (no idea if this was due to Airdroid or Ubuntu) that caused a problem when transferring files to my computer. When I tried to transfer multiple files, Airdroid would put them into a .ZIP file. After transferring that .ZIP file, I'd extract them into a folder. But when I tried to open one of the files, I received the following error message: "Failed to open input stream for file." However, if I tried to download the files one at a time, everything was fine. The files would open normally. It was only if I tried to download multiple files at once that this error occurred.
I went to the Airdroid support forum to see if anyone else was having this problem. Yes, someone was. The Airdroid admins also said (a) that they were aware of the problem, (b) it was a bug, and (c) they would correct it with the next update. But the temporary answer to this problem for those of us running Ubuntu was in this snippet:
You don't have the permission to open the pictures you download. A temporary solution is to use some permission management to get the permission.
In a word, bingo! So here's how to fix this problem until Airdroid issues the permanent fix:
- Use Airdroid to download the multiple files as you would normally do.
- Open the .ZIP file and extract the files to a folder in Ubuntu.
- Select all of the files so that they are highlighted.
- Right-click on any of the highlighted files. This will bring up a menu.
- At the bottom of the menu, select "Properties".
- This will bring up a pop-up window. At the top, select the "Permissions" tab.
- If your situation is similar to mine, the user choice probably says, "No read, no write". Click on this drop-down menu and select "Read and write".
- If you want to, the next one down (for "Group") also probably says "no read, no write". Click on that drop down menu and select "Read and write".
- At the bottom of the window, click on "Close".
That should do it. You should now be able to work with the files normally. Again, it's just a permission problem. But this should fix this until Airdroid issues the permanent fix sometime later.