UNIX for Dummies Questions & Answers

chmod 754 file3 would yield the same as:

Code:

 chmod u=rwx, g=rx, o=r file3

Code:

chmod u+rwx, g=rx, o=r file3

the first one is what i put the second is what was correct.
i guess i'm asking what is the difference with "+" and "=" and how do you know when to use either.

On my system both of the commands are syntax errors.

What permissions change do you wish to achieve?

i forgot to keep them together like so

Code:

chmod u=rwx,g=rx,o=r file3

Code:

chmod u+rwx,g=rx,o=r file3

I just don't understand the difference between the two, when i use both. they "appear" to do the same thing. like what is the point of using "+" or "-" when "=" does the same thing, if i'm getting at this right.

i want:
user: to read,write, and execute.
group: to read and execute.
other: to only read.

The "=" version is setting the permissions regardless of any previous permisssions. The "+" version is adding permissions to existing permisisons.
As the permissions in your example are "rwx" the two are pretty much interchangeable.
However if the orginal permissions were "srwx" the "=" version would unset the SUID bit.
The two commands are actually different.
Hope this helps.

It is so much better to positively set permissions on a file. Never used the "+" version of the command in a commercial environment myself.

ok I see why now then. Thanks!^