Can we able to Edit/Create a file using 'File Permission'?

Question

Is there any Way to Edit/Create a file in the method of File Permission ?

Suppose it is '7' means can we able to change it to '4' ?

i.e -rwx to -r ?

Is there any code or___ to do?

Eric Power · Accepted Answer · 2015-08-12T07:26:03.720

2

I believe you are looking for chmod. This command allows you to change permissions for a file.

Say you want to change the permissions of ./foo.txt to '4' then it's chmod 4 ./foo.txt

If you want to do this to all the files in a directory it would be chmod 4 *.

If you wanted to do this recursively through all files and directories somewhere it would be chmod -R 4 *

If you wanted to revert the change back to '7' on a file, it would be chmod 7 ./foo.txt. You can also use * or -R this way to change permissions on more than one file.

Click here for the chmod man pages.

Occasionally you will need to run sudo chmod instead of just chmod. Originally I had it as sudo chmod everywhere, however it is a bad habit to get into to use sudo when you don't need to.

edited Aug 12 '15 at 07:26

answered Aug 09 '15 at 07:07

Eric Power

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Yes, you are right ! ,Thanks a lot @ Eric power. But can we able to do it to all the files and how to revert it ..? – Madhusudhanan Aug 09 '15 at 07:16
I edited my answer, is that what you mean? – Eric Power Aug 09 '15 at 07:39
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-1: chmod doesn't always need sudo. – muru Aug 09 '15 at 07:50
thanks to all.. I mean if we don't know the chmod of a file but we have changed it ! Can we able to revert it @ Eric Power? – Madhusudhanan Aug 09 '15 at 07:55
Hmm, not that I'm aware. I believe you would have to write a script that would check the permissions and save them somewhere, and then when you want to revert them read from wherever you saved it and revert to that level. – Eric Power Aug 09 '15 at 08:08
@EricPower Good answer but how about addind a link tho the chmod manpage ? – Mark Kirby Aug 09 '15 at 08:23
Sure, although I typically use the man chmod command. – Eric Power Aug 09 '15 at 08:38
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Sure, just noob friendly to add link, I like this now +1 – Mark Kirby Aug 09 '15 at 08:59
Good point, I'll start doing that from now on. – Eric Power Aug 09 '15 at 09:02
@markkirby in that case, link to the Ubuntu manpages, since these are generated from the packages available for Ubuntu. For chmod, it might not make much difference, but for other commands, it could. – muru Aug 09 '15 at 09:11

Can we able to Edit/Create a file using 'File Permission'?

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