How to delete a write protected file
Reader Ashish asks "How to delete write protected file under Linux..."
Under Linux (and other Unixsh oses) following criteria should matched before deleting a file:
Criteria # 1
To delete or remove a file you need to be owner of a file. Use ls -l command to verify your ownership:
$ ls -l filename
If you have sufficient rights, you can remove a file. Otherwise, become a superuser to remove a file.
Criteria # 2
In addition, you must have a write access to on a directory that allows you to remove or add new files. Again us ls -l or ls -ld command to get write ownership of directory.
$ ls -ld dirname
If you have sufficient rights, you can remove a file. Otherwise, become a superuser to remove a file. Use chown / chmod commands to setup permission OR run rm command as root user:
# su -
# rm -f file.txt
Criteria # 3
Make sure file is not protected using extended file system 'i' attribute. A file with the 'i' attribute cannot be modified, it cannot be deleted or renamed, no link can be created to this file and no data can be written to the file. Only root can add or remove 'i' attribute. Use lsatter command to verify that file is not write protected using extended 'i' attribute:
$ lsattr file.txt
Output:
----i------------ file.txt
Above output indicates that file.txt has i attribute set on it. Become a superuser and follow the instruction mentioned here to remove a write protected file:
# chattr -i file.txt
# rm -f file.txt
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Your commands are slightly incorrect. Change chattar to chattr and lsattar to lsattr.
They stand for “CHange ATTRibute” and “LiSt ATTRibute”
Indeed
Apologies for the typo.
sir, my sd card neither copy files from another source not deleting file from it. Kindly suggest a method to solve my problems.
can u use that
in deepfreeze
without knowing the password
can u delete deepfreeze just like that
it is write protected
and then theres password when you need to disable
is there any other method deleting write protected file
On the Mini SD adapter, there is a lock tap you push down usually when you put your mini SD card in to it, then into the USB adapter. To turn off the write protection on your mini SD, simply do not lock your mini SD in its adapter.
ok i had the same problem i downloaded a patch from a peer 2 peer site and it was’nt wot i wanted
and tried to delete it but it said it was write portected so i just tried to just stuff it up as much as i could just playin round with its properties and here is wot i came up with GO INTO PROPERTIES OF THE FILE THEN CLICK ADVANCED MAKE SURE THE BOXES THAT SAY…… FILE IS READY FOR ARCIVING,……FOR FAST SEARCHING ALOW INDEXING SERVICE TO INDEX THIS FILE AND…. COMPRES FILES TO SAVE DISC SPACE .. ARE ALL UNCHECKED THEN CLICK OK THEN GO TO THE PART THAT SAYS ….READ ONLY AND TICK IT THEN PRESS OK IT SHOULD EXIT IF ANY ERRORS COME UP THEN JUST CLICK OK THEN TRY DELETEING IT IT WORKED 4 MEHOPE IT DOES 4 ALL U PPL 2 NOTE:I DONE THIS WITH A FILE NOT A FOLDER SO DONT EXPECT IT TO WORK ON FOLDRES I DONT EVEN KNOW IF IT WORKS ON ALL FILES IT JUST WORKED 4 ME AT THE TIME AND WHEN I SEARCHED HOW TO FIX IT IT DIDENT REALY GIVE ME A CLEAR ANSWER ANYWAY E MAIL ME AND TELL ME HOW U WENT at dime_megga@yaoo.com.au 1 more note remember to close all programmes that even could b useing it even shut down your torrent if u have to before u try to get rid of it ok c ya sorry bout the typos
Thanks! Becoming su and using the command
rm -f filename worked. I am using an mp3
player as a card reader to transfer files between
computers (one Red Hat 7.2 and the other FC3),
and I have never had this problem (not being
able to delete a file just by clicking and
choosing “move to trash”) before. It is very odd.
I have not changed permissions on any of the
devices. It is not the card reader (i.e. mp3
player) because I had the same problem with 2
different ones. Do old SD cards often do this?
Mine isn’t even that old and does not get heavy
use. Thanks again for all the useful advice.
@Jashawn Ram:
If your system has automounted the SD card, you may find that everything from its mount point down is owned by root. if you’re trying to remove or write files to the SD you’ll either have to:
1) Do it as root.
2) As root, change the ownership recursively on the SD to your personal account.
EX. chown -R matt:mattgrp /the/path/to/your/SDcard