More on changing the Gnome clock

In my previous post about the Gnome clock, I showed you how to change the clock from the default 24 hour time display to a 12 hour format. In this post, I will show how you can change things to display seconds as well. Here is my default display string in gconf-editor:

%a %b %d, %l:%M %p

From reading the date manpage, you know that this will display the Year, month, day, hours and minutes. Something like this: Sat May 01, 5:16. But what about seconds? If you want that, just add the appropriate specifier (%S) to the date string:

%a %b %d, %l:%M:%S %p

Note: You will also need to check the 'show_seconds' box roughly 11 places below the date string setting in gconf-editor. If you forget this part, the seconds portion will display, but the numbers will not actually change until the minutes portion changes because the clock isn't being updated every second.

What I have been doing.

For the past few minutes, anyway...

(a+b)^7
= (a+b)(a+b)(a+b)(a+b)(a+b)(a+b)(a+b)
= (a^2 + ab + ab + b^2)(a+b)(a+b)(a+b)(a+b)(a+b)
= a(a^2 + ab + ab + b^2) + b(a^2 + ab + ab + b^2)(a+b)(a+b)(a+b)(a+b)
= a^3 + a^2b + a^2b + ab^2 + a^2b + ab^2 + ab^2 + b^3 (a+b)(a+b)(a+b)(a+b)
= (a^3 + 3a^2b + 3ab^2 + b^3)(a+b)(a+b)(a+b)(a+b)
= a(a^3 + 3a^2b + 3ab^2 + b^3) + b(a^3 + 3a^2b + 3ab^2 + b^3)(a+b)(a+b)(a+b)
= (a^4 + 3a^3b + 3a^2b^2 + ab^3 + a^3b + 3a^2b^2 + 3ab^3 + b^4)(a+b)(a+b)(a+b)
= (a^4 + 4a^3b + 6a^2b^2 + 4ab^3 + b^4)(a+b)(a+b)(a+b)
= a(a^4 + 4a^3b + 6a^2b^2 + 4ab^3 + b^4) + b(a^4 + 4a^3b + 6a^2b^2 + 4ab^3 + b^4)(a+b)(a+b)
= (a^5 + 4a^4b + 6a^3b^2 + 4a^2b^3 + ab^4 + a^4b + 4a^3^b2 + 6a^2b^3 + 4ab^4 + b^5)(a+b)(a+b)
= (a^5 + 5a^4b + 10a^3b^2 + 10a^2b^3 + 5ab^4 + b^5)(a+b)(a+b)
= a(a^5 + 5a^4b + 10a^3b^2 + 10a^2b^3 + 5ab^4 + b^5) + b(a^5 + 5a^4b + 10a^3b^2 + 10a^2b^3 + 5ab^4 + b^5)(a+b)
= (a^6 + 5a^5b + 10a^4b^2 +10a^3b^3 + 5a^2b^4 + ab^5 + a^5b + 5a^4b^2 + 10a^3b^3 + 10a^2b^4 + 5ab^5 + b^6)(a+b)
= (a^6 + 6a^5b + 15a^4b^2 + 20a^3b^3 + 15a^2b^4 + 6ab^5 + b^6)(a+b)
= a(a^6 + 6a^5b + 15a^4b^2 + 20a^3b^3 + 15a^2b^4 + 6ab^5 + b^6) + b(a^6 + 6a^5b + 15a^4b^2 + 20a^3b^3 + 15a^2b^4 + 6ab^5 + b^6)
= a^7 + 6a^6b + 15a^5b^2 + 20a^4b^3 + 15a^3b^4 + 6a^2b^5 + a^6b + a^6b^2 + 6a^5b^2 + 15a^4b^3 + 20a^3b^4 + 15a^2b^5 + 6ab^6 + b^7
= a^7 + 7a^6b + 21a^5b^2 + 35a^4b^3 + 35a^3b^4 + 21a^2b^5 + 7ab^6 + b^7


OpenSUSE 11.2: My best Linux experience by far.

Over the years I have been through a few different Linux distributions.  I ran Mandrake (hey, I was really a n00b) for a bit.  Then I caught the Gentoo bug (no, I was not a ricer, but I did really like their helpful forums and wiki pages) and did that for quite a few years.  Then something went wrong with my system, and I lost the drive.  I didn't have time to fiddle with restoring everything, so I slapped Fedora 11 on it.  It was the Fedora install that got me thinking that I kind of enjoyed it when everything seemed to work, right out of the box.   In fact, I was so pleased with the way it all worked so well, that I installed it on both of my computers.  I liked the fact that I didn't have to spend hours trying to make things work.  Someone once said, "Linux is only free if your time is worth nothing."

Changing Gnome panel clock from 24hr time to 12hr time on OpenSUSE 11.2

Fire up your shell, and type in gconf-editor.  Then, on the left, select Apps --> panel --> applets --> applet0 --> prefs (This was slightly different for me between two different machines.  It might be ...applets --> clock_screen0 --> prefs.)  First you want to right click on 'format' on the right side of the gconf-editor, and select 'Edit Key'.  In the dialogue box that comes up, enter 'custom' (without the quotes).  Then click ok.  Next, you will need to enter 'custom_format' (about 6 entries above 'format').  Again, right click and select 'Edit Key'.  Here you will enter <b>%a %b %d, %l:M %p</b> and click ok.  This will get you a format such as Thu Jan 28, 12:20.  If you prefer a different format, look at some of the options available in the date man page.

Read more here.  (Don't forget to look at the comments section at the bottom as well).

Shell shortcuts part deux.

In my last post, I demonstrated how you can use the !! and !$ features of your Bash & zsh history to get your work done more quickly.   I use the former all the time, but  the latter?  Well, not so much.  This is because I use something even better for interactive shell use.  It is M-.  That is Meta plus period.  All you Emacs zealots users will know what I mean by Meta.  :)  The Meta-key is Alt on your computer, or sometimes Esc.  Both work on my machine, but I prefer Alt over Esc, because it is less work.

Try doing M-. in your shell (Press and hold the Alt key, and then press the period key).  Like !$, M-. will give you the last part of the last command entered, but this time you can see it immediately.  Better still, you can cycle through all of your commands.  Just keep hitting M-. and the shell will display the last part of each command, in order, from newest to oldest.

Note:   If you use the ESC key for your 'Meta' key, then you need to release the ESC key each time.  Otherwise, if you hold it down and tap the . (period) key, it will return the end of the last command only once, and then start echoing the period after it.

As an example, say you had just finished a

grep fred /etc/passwd

You are ready to use the command line history feature:

vi M-.

Which would expand to (immediately):

vi /etc/passwd

Then, if it looks right, just press Enter.

Shell shortcuts

In Bash and zsh, you can access the command history by using several shortcuts.  For example, by typing !![Enter], the previous command will be executed.  If you are not sure of what the previous command was, you could do !!:p[Enter] and the previous command will be displayed, but not executed.  Now, if you like what you see, you can do !![Enter], and the shell will execute that command.

Another ! shortcut is !$.   This will give you the end of the previous command.  So if my previous command was:

grep fred /etc/passwd

doing !$ would give me /etc/passwd.  This can be handy.  Say for example the user fred exists on the system, and grep returns his record from /etc/passwd.  If there is something I see in one of the fields that I wish to change, all I need to do (provided that grep was the last command I did) is:

vi !$

This will expand to

vi /etc/passwd

If you are not sure how !$ will expand for you (ie., you cannot remember for certain what your last command was exactly), you can use the :p option:

vi !$:p

Pagers

I won't give you a history of documentation viewers (aka pagers) on *nix systems, other than to say that there used to be pg and more. Then along came less, which was a lot like more, but way better.  Apparently there is a play on words there, so maybe it is true that less is more.

Anyway, I have long followed the advice to use the less pager where it is available.  I don't follow that advice strictly any more.  I now use most. From the most home page:

"MOST is a powerful paging program for Unix, VMS, MSDOS, and win32 systems. Unlike other well-known paging programs most supports multiple windows and can scroll left and right. Why settle for less?"

Indeed.