File permissions?

[Jim Byrnes]

Johnny Rosenberg wrote:
> 2009/12/25 Jim Byrnes <jf_byrnes at comcast.net>:
>> Johnny Rosenberg wrote:
>>> 2009/12/25 Jim Byrnes <jf_byrnes at comcast.net>:
>>>> I've been using Ubuntu for about two weeks now and am starting to get
>>>> used to it.  However, coming from an OS/2\Windows world file permissions
>>>> seem to be giving me some grief.
>>>>
>>>> Maybe if someone could tell me how to do a couple of specific tasks it
>>>> would become clearer to me.  I have Jedit loaded on all three of my
>>>> OS's. I have modified some mode files on the other OS's I would like to
>>>> use on Ubuntu.  I copied them to a shared folder on Ubuntu but I can't
>>>> copy them to /usr/share/jedit/modes which is where Jedit will look for them.
>>> Is there a special reason why the files have to be located there? For
>>> most tasks, your personal files should be located somewhere in your
>>> home directory (home folder), called $HOME, which is an environment
>>> variable containing the address of your home folder. The ”~” means the
>>> same thing. So ~/MyFolder is the same thing as $HOME/MyFolder, which
>>> is the same thing as /home/Jim/MyFolder if your user name is Jim.
>>> If you still want to place your file at /usr/share/jedit/modes you
>>> have to do it with root permissions, unless you want to change the
>>> owner of the folder.
>> They were put there by the installaion of Jedit.  They are really not
>> personal files.  They control syntax highlighting depending upon the
>> type of file you are editing.  I just modified a couple of them to suit
>> my taste.
> 
> Oh… in that case I would just edit them by opening them in my
> favourite editor as root in the terminal, for instance:
> 
> gksudo gedit /usr/share/jedit/modes/FileName
> 
> Since you say you are a beginner, I will also mention the convenient
> use of the ↹ key (TAB) (hopefully this message will not be ”converted”
> with another character encoding than UTF-8, otherwise you can't see my
> TAB characters and it will look somewhat confusing…). To input the
> line above, you will probably only need to do this:
> 
> gk↹s↹ ge↹ /u↹sh↹je↹m↹/Fi↹↵
> 
> ↹ expands what you typed so far. If there are several possibilities to
> expand, you can hit ↹ twice to see the options.

I see the tabs but it took me a couple of readings before I realized 
exactly what you were demonstrating for me.

>  You can copy, cut and paste in the terminal, but the default
> shortcuts are Shift+Ctrl+x, Shift+Ctrl+c and Shift+Ctrl+v rather than
> just Ctrl+x, Ctrl+c and Ctrl+v. Of course you can change this if you
> want to: Edit → Keyboard shortcuts.
> 
> And you can use ↑ and ↓ if you want to walk through the commands
> history. ↑ taking you one command backwards and ↓ is the other way, of
> course.
> 
> Oh, and another thing: The & operator puts the process in the
> background, for example:
> 
> gedit MyFile&
> 
> This will open gedit with MyFile and the terminal isn't locked to it
> while I am editing MyFile, so I can use it for other things at the
> same time, not needing to open another terminal. The terminal first
> outputs the process ID for you, in case you want to kill the process:
> kill 23596
> (if the process number was 23596).
> 
> Well, what's more? A lot, of course… it's also convenient to know
> about the <, > and >> operators.
> 
> free -m > MyFile
> This redirects the output of the free -m command to the file MyFile.
> If the file exists it will be erased, created and filled with the data
> from the command. If it doesn't exist it will be created and filled
> with the data.
> 
> free -m >> MyFile
> Data from free -m will be added at the end of MyFile.
> 
> The < goes the other way around: It use a file for sending data to the command.
> 
> To look at your textfile the ultra simple way, try this:
> cat MyFile
> 
> If the file is big, one of these will be more convenient:
> more MyFile
> less MyFile
> 
> I prefer ”more”, but most people prefer ”less” I think, You decide
> what you prefer. Both commands views the file page by page. To see the
> next page, hit SPACE. Or ↵ I think.
> Try this simple way to create a text file:
> 
> cat > MyTextFile
> Hello world!
> Hello people!
> Ctrl+d
> 
> cat MyTextFile
> 
> To erase files, use the rm command (ReMove):
> rm MyTextFile
> rm MyFile
> 
> If you want to know more about a command, like rm for instance, do:
> man rm
> 
> If you are not sure what command to use when, let's say you want to
> remove a file, try:
> man -k remove
> (-k as in ”keyword”)
> 
> To quit the man command, just hit q to get back to your prompt.
> alias is also a useful command. Maybe you think it's too much typing
> to hit ”ls -lB --si” everytime you want to view the contents of a
> directory. This will make it easier:
> alias ll='ls -lB --si'
> From now on, just type ”ll” for doing the same thing.
> When you log out and login again, your aliases will be forgotten, so
> you need to put all your aliases in a file that is run at every
> startup. ~/.bashrc is a good one. Personally I created my own alias
> file, ~/.bash-aliases, which I start from the ~/.bashrc file by just
> adding the following lines in ~/.bashrc:
> 
> if [ -f ~/.bash-aliases ]; then
>     . ~/.bash-aliases
> fi
> 
> The alias file will then be started only if it exists.
> There are a few aliases pre defined. I moved mine to the alias file.
> 
> To see all your aliases, try:
> alias
> 
> To remove an alias:
> unalias
> 
> And we also have the beloved | character (pipe character).
> 
> Try this, for instance:
> ps -e
> 
> Now try this:
> ps -e | grep gnome
> 
> The last command only shows lines that contains the string ”gnome”.
> See man ps and man grep for more details.
> 
> Well, that's all for now, I guess… I guess it would be better to point
> to a link or something, so I'll do that too:
> http://www.gnu.org/software/bash/manual/bashref.pdf
> 
> 
> Johnny Rosenberg
> 
>>> You can do most things with a GUI and since other people have
>>> suggested doing it in the terminal, I will try to keep more to a GUI.
>>> If you don't have an icon for opening Nautilus (your file manager)
>>> with root permissions, open a terminal (!) and enter:
>>> gksudo nautilus
>>> (sudo nautilus will also do, but then you need to enter your password
>>> in the terminal instead of doing it in a dialogue…)
>>> Now look for your files and move them where you want them.
>>> When they are where you want them, right click them and click
>>> Properties, then click the permissions tab. Here you can change the
>>> owner of the file as well as the permissions. After changing the owner
>>> to yourself and given yourself the proper permissions, you should be
>>> able to do what you want with them with jedit.
>>>
>>> If you don't have a icon for ”Nautilus as root”, you can easily create
>>> one. Ask if you can't figure out how.
>>>
>>> Johnny Rosenberg
>>>
>> Thanks for the info on the gui way to do it.  Sometimes the terminal can
>> be a little overwhelming to a newbie.
>>
>> Regards,  Jim
>>
>>>> In that same vein, if I wanted to edit one of those files with Jedit how
>>>> could I get Jedit to open it for editing?

Thanks, I'll add this to my growing list of helpful email messages.

Regards,  Jim