[FM Discuss] Book idea: useful command lines

[Jeffrey Osier-Mixon]

Hi all

I suggest an FAQ format rather than a manual.  I am much more often 
asked "how do I do X" than "what does this command do".  Subsequent 
entries can build on previous ones. 

Here is a lame example:
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Q: Of the hundreds of random text files on my desktop, how can I 
determine where I wrote down how to spell my new niece's name?

$ cd $HOME/Desktop; grep niece *

That didn't locate anything.  I don't think I used the term "niece", but 
my brother's name is George.

$ grep George *

Q: That didn't work either, and her first birthday is coming up!  What 
shall I do?  What shall I do?

$ grep -i george * | grep -i daughter
to-do1234.txt: george's daughter's name is Ezmerelda
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The trick is figuring out what people are going to want to do, and 
presenting the items in a logical order rather than just a random list 
of "how do I" entries.  This example is about guessing what one's past 
self might have used as a search term that the future self would 
remember, but it might make sense to then follow up with better advice, 
and then explain what is going on in the example. 

___________________________________________________________________
Q: How am I going to remember her name and birthday in the future?

One method is for your computer to remind you.  This example uses 
<code>cron</code>, a daemon that runs in the background and performs 
periodic tasks.  First, create a temporary text file to hold the entry 
(see "man 5 crontab" for details on cron entry syntax).  The example 
shows storing a message in a temporary file and then popping it up at 
the appropriate time, in this case noon on November 15 of any year.  
Then install the new entry by running the <code>crontab</code> command.

$ cat > new-cron
0 12 15 11 * 'cat "Ezmereldas birthday coming up on 12/1" > /tmp/foo ; 
xmore -display :0 /tmp/foo ; rm /tmp/foo'
^D
$ crontab ./new-cron

Note that these commands create a new crontab entry file, erasing 
previous entries.  To add more entries, or to edit this one:

$ crontab -e

To list all of your cron entries:

$ crontab -l
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I would further suggest that this valuable subject could be best covered 
in a wiki rather than in a manual, so that readers can contribute by 
asking questions that the authors won't have considered.

I hope this is useful!


adam hyde wrote:
> i think this project, and Micks summation of the tourists guide to the
> command line is cool...it might be interesting to send out emails asking
> for peoples one-liners...there would be a tonne of interesting one
> liners out there that i am sure people would like to contrib...formating
> a good email and sending (where appropriate) to some lists might yield
> interesting returns
>
> shall we create an empty manual for this? if so, what do we call it?
>
> adam
>