Attend XDA's Second Annual Developer Conference, XDA:DevCon 2014!
5,785,865 Members 50,794 Now Online
XDA Developers Android and Mobile Development Forum

unable to write files to external sd card

Tip us?
 
otamctech
Old
#21  
Member
Thanks Meter 8
Posts: 45
Join Date: Jul 2011
Location: Philly PA
Quote:
Originally Posted by thaloneus View Post
I can't post a link to the original post on another forum that worked for me so I will quote it:

Simple solution for external sdcard write access on Android 3.2...if you're rooted

I've found a simple solution for gaining write access to the external sdcard (/mnt/sdcard2) on Android 3.2. The sdcard is mounted r/w, but the owning group is media_rw which is linked to the WRITE_MEDIA_STORAGE permission. Unfortunately, this permission was not required for access to the external sdcard prior to 3.2 so most file management utilities do not request it when they run...meaning they only have read access to the card.

The simple solution, if you're rooted, is as follows:
1. Using a root-enabled file manager, navigate to /system/etc/permissions and make sure you have mounted the file system r/w.
2. Edit platform.xml and find the WRITE_EXTERNAL_STORAGE permission.
3. Add an additional group definition for this permission...<group gid="media_rw" />
4. Save the changes to the file.
5. Restart your tablet.

After this change, any apps that request the WRITE_EXTERNAL_STORAGE permission (which includes almost anything that access either of the sdcards) will gain group membership in both sdcard_rw AND media_rw, giving them r/w access to both sdcard filesystems.
Good Stuff - worked for me. Thanks.
 
KnoxBNYC
Old
#22  
KnoxBNYC's Avatar
Senior Member
Thanks Meter 57
Posts: 274
Join Date: Dec 2011
Location: New York, NY
Quote:
Originally Posted by boonhim View Post
Please someone provide me more details or give me the picture of the edited .xml thanks.

Sent from my GT-P6200L using Tapatalk
This is my screen shot. After pulling my hair out over my Tab 7;0 Plus not being able to write to its SD card, I tried this idea from this forum and it worked like a charm!!

(See the top line of the screen cap.)

Knox B.
Attached Thumbnails
Click image for larger version

Name:	export_02.jpg
Views:	2196
Size:	46.3 KB
ID:	858832  
 
KnoxBNYC
Old
#23  
KnoxBNYC's Avatar
Senior Member
Thanks Meter 57
Posts: 274
Join Date: Dec 2011
Location: New York, NY
Quote:
Originally Posted by thaloneus View Post
I can't post a link to the original post on another forum that worked for me so I will quote it:

Simple solution for external sdcard write access on Android 3.2...if you're rooted

I've found a simple solution for gaining write access to the external sdcard (/mnt/sdcard2) on Android 3.2. The sdcard is mounted r/w, but the owning group is media_rw which is linked to the WRITE_MEDIA_STORAGE permission. Unfortunately, this permission was not required for access to the external sdcard prior to 3.2 so most file management utilities do not request it when they run...meaning they only have read access to the card.

The simple solution, if you're rooted, is as follows:
1. Using a root-enabled file manager, navigate to /system/etc/permissions and make sure you have mounted the file system r/w.
2. Edit platform.xml and find the WRITE_EXTERNAL_STORAGE permission.
3. Add an additional group definition for this permission...<group gid="media_rw" />
4. Save the changes to the file.
5. Restart your tablet.

After this change, any apps that request the WRITE_EXTERNAL_STORAGE permission (which includes almost anything that access either of the sdcards) will gain group membership in both sdcard_rw AND media_rw, giving them r/w access to both sdcard filesystems.
@thaloneus :

Thank you SOOO much for this.

But, I have to frickin' ask:

Is this a bug?

An oversight on Samsung's part?

A problem with Honeycomb?

Do other Honeycomb devices have the same problems?

Do all Honeycomb devices have this problem??

 
garyd9
Old
#24  
garyd9's Avatar
Recognized Developer
Thanks Meter 1,979
Posts: 1,951
Join Date: Sep 2006
Location: Pittsburgh, PA
Quote:
Originally Posted by KnoxBNYC View Post
But, I have to frickin' ask: ... Is this a bug? ...
Do all Honeycomb devices have this problem??
Not a bug. Its a design change with honeycomb that very few (if any) app developers have caught up with. I think that at least some tablet makers have modified that .xml file in their stock firmware, but certainly not all of them.

Gary

Donations: I don't accept donations, but if you are feeling charitable, help a child by going to http://www.shrinershospitalsforchildren.org/
and click the "Donate Now" link at the top.
 
SuperBoUDS
Old
#25  
SuperBoUDS's Avatar
Senior Member
Thanks Meter 49
Posts: 155
Join Date: Jan 2012
Quote:
Originally Posted by thaloneus View Post
The simple solution, if you're rooted, is as follows:
1. Using a root-enabled file manager, navigate to /system/etc/permissions and make sure you have mounted the file system r/w.
2. Edit platform.xml and find the WRITE_EXTERNAL_STORAGE permission.
3. Add an additional group definition for this permission...<group gid="media_rw" />
4. Save the changes to the file.
5. Restart your tablet.

After this change, any apps that request the WRITE_EXTERNAL_STORAGE permission (which includes almost anything that access either of the sdcards) will gain group membership in both sdcard_rw AND media_rw, giving them r/w access to both sdcard filesystems.
I have the same problem and this tip work for me. Thank u for useful tip .
 
Sigilist
Old
(Last edited by Sigilist; 20th January 2012 at 04:06 PM.) Reason: UPDATE
#26  
Junior Member
Thanks Meter 0
Posts: 12
Join Date: Mar 2011
I'm afraid this didn't work for me. I'm a bit new to working with an android device, but I have rooted the unit, and then acquired root explorerer, and then carefully edited the xml file noted. I rebooted and still cannot write to the extSD.

When I went back into the xml file, I noted that in place of two "group" tags (including the one I added for "media_rw"), only the one I added was in the permissions group noted. The one that was there when I edited is now gone. Even root explorer was not able to test create a new folder on the extSD.

Any suggestions?

CORRECTION: I can now navigate to the extSD and create folders via root explorer. But so far, other file managers (beyond the systems default) do not seem able to do so. Strange (to me). This also means I cannot copy and paste files either except through root explorer (which is sort of unfriendly to this newb vs. other file managers).
 
zetajunkie
Old
#27  
zetajunkie's Avatar
Senior Member
Thanks Meter 5
Posts: 190
Join Date: Apr 2006
Location: Brooklyn, NY
Quote:
Originally Posted by Sigilist View Post
I'm afraid this didn't work for me. I'm a bit new to working with an android device, but I have rooted the unit, and then acquired root explorerer, and then carefully edited the xml file noted. I rebooted and still cannot write to the extSD.

When I went back into the xml file, I noted that in place of two "group" tags (including the one I added for "media_rw"), only the one I added was in the permissions group noted. The one that was there when I edited is now gone. Even root explorer was not able to test create a new folder on the extSD.

Any suggestions?
My solution was to use a different text editor than stock (used "Text Edit," free through market) after using Root Explorer to set the folder to r/w (read/write). I had no luck using the stock editor...
Samsung Galaxy S4 - root
Samsung Galaxy Tab 7.0+ (GT-P6210) - root
HTC EVO 4g - root, s-off, deck 1.3 stable
 
KChauJen
Old
#28  
Senior Member
Thanks Meter 9
Posts: 398
Join Date: Jan 2004
Following the instruction, I can write to the External-SD card with Root Explorer, but if you reboot your table, whatever in there would be gone...

Does it happens to You?

Thanks
Samsung Galaxy Note 3 SM-N9005
In Search of the best modified firmware

Samsung Galaxy Note 8
In Search of the best modified firmware

Samsung Galaxy Note II GT7100
Android 4.3
 
StingerDog
Old
#29  
Member
Thanks Meter 12
Posts: 49
Join Date: Dec 2011
Quote:
Originally Posted by KChauJen View Post
Following the instruction, I can write to the External-SD card with Root Explorer, but if you reboot your table, whatever in there would be gone...

Does it happens to You?

Thanks
It does not.

I almost forgot this important step when I edited the file:

"The simple solution, if you're rooted, is as follows:
1. Using a root-enabled file manager, navigate to /system/etc/permissions and make sure you have mounted the file system r/w.
2. Edit platform.xml and find the WRITE_EXTERNAL_STORAGE permission.
3. Add an additional group definition for this permission...<group gid="media_rw" />
4. Save the changes to the file.
5. Restart your tablet."

Check to make sure you are saving the edit before you reboot.
The Following 2 Users Say Thank You to StingerDog For This Useful Post: [ Click to Expand ]
 
KChauJen
Old
#30  
Senior Member
Thanks Meter 9
Posts: 398
Join Date: Jan 2004
Quote:
Originally Posted by StingerDog View Post
It does not.

I almost forgot this important step when I edited the file:

"The simple solution, if you're rooted, is as follows:
1. Using a root-enabled file manager, navigate to /system/etc/permissions and make sure you have mounted the file system r/w.
2. Edit platform.xml and find the WRITE_EXTERNAL_STORAGE permission.
3. Add an additional group definition for this permission...<group gid="media_rw" />
4. Save the changes to the file.
5. Restart your tablet."

Check to make sure you are saving the edit before you reboot.
Oh yeah!!! of course, if it doesn't, then it can't be created on the new files or folder in external storage.

Double check again, created the new text file on the root of "extStorages", then reboot.... result: File is gone

FYI
Samsung Galaxy Note 3 SM-N9005
In Search of the best modified firmware

Samsung Galaxy Note 8
In Search of the best modified firmware

Samsung Galaxy Note II GT7100
Android 4.3

The Following User Says Thank You to KChauJen For This Useful Post: [ Click to Expand ]
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes