One of the cool features of IMAGE BBS and C-NET was displaying fun and witty sayings during the login process (On older versions of C-Net I believe this was referred to as a Fortune Cookie.

Image BBS Random Saying (Screen Shot From Commodore Image BBS)

In some ways, especially if you login to a UNIX/LINUX box via a terminal, it looks just like a giant BBS. I thought it would be fun to duplicate this feature on my Linux development box. It will also give me the opportunity to introduce to you login scripts or “Profiles”, as well as basic file manipulation.

The last 2 BASH demonstrations were taken from Commodore 64 BASIC programs, and from an IMAGE BBS +. File, so let’s switch gears here, and take our source from a CNET Amiga 3.5c module that was written by Jim Selleck of Beverly James Products. This module was included on the CNET 3.05c Demo and Productions disks, and the comments state it originated with C-Net Amiga 2.0.

Before we begin I would like to throw out a quite plug for C-Net Amiga 3, and the brilliant work done by its author Ken Pletzer. C-Net Amiga 3.05c happened to be one of the most stable, customizable, and feature rich BBS software that I had a pleasure to run. This particular module was written in ARREX, which was an Amiga port of the REXX scripting language developed by IBM and included with Amiga DOS 2.0. There is a version of REXX that will run under Linux. So maybe in the future we could actually explore some native REXX scripts running under Linux itself.

Lets quickly take a look at the original source, as REXX, and it’s features under C-Net Amiga are pretty straight forward and lend itself to very easy porting into BASH.

/******************************************************/
/* Random Quotation Generator 2 for CNet AMIGA v2 */
/* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */
/* By Jim Selleck © 1992 Beverly James Products */
/* */
/* Installation: */
/* */
/* Stick this Arexx program and the QUOTATIONS file */
/* in your PFILES: directory. */
/* #*/
/******************************************************/

options results
filename = “pfiles:quotations”

if ~exists(filename) then

do
transmit ” ”
transmit ” ”
transmit “The Quotations could not be found! Please inform”
transmit “the Sysop !!!”
transmit ” ”
transmit ” ”
logentry “Quote: `”||filename||”‘ not found!”
exit
end

call open quote,filename,”R”

max = readln(quote) /* Get maximum number of entries */
num = random(0,max-1,time(‘s’))
ctr = 0

if num > 0 then
do until ctr = num*5
line = readln(quote)
ctr = ctr+1
end

transmit ” ”
transmit ” ”
ctr = 0

do until ctr = 5
line = readln(quote)
if length(line) > 1 then transmit center(strip(line),76)
ctr = ctr+1
end

call close quote
exit

The lines in the /* */ are simply comments, similar to BASH pounds #

Filename = is simply setting the path to the quotations filename in this case “PFILES:quotations”
We then have the script saying, if the file does not exist ~exists, then output the text asking the user to inform the SysOp (System Operator).

‘logentry’ is a specific CNET AREXX function that will write an entry into the systems caller log.

The next line is  opens the quotations file, and then reads the first line, which will specify the number of quotes, Which is 100. Then the result ‘num’ will be a random number between 1 and the number of MAXQUOTES.

The file is then read from line X for 5 more lines, and is center justified for a 79 character line.  So we have a 500 line text file, each 5 lines is a record, containing the quote and the source.

Here is our simple BASH script called ‘rand_quote.sh’. The quotations file was read directly from CNET Amiga using the WinUAE emulator and saved to a capture file.

Let’s now take a look at our BASH script. I would recommend creating this in a dev folder in your home directory, once tested you can move it in to the proper folder.

You must also download the quotations file, from the following link.
https://www.catracing.org/hendrb/wp-content/uploads/2015/06/quotations.txt
1 #! /bin/bash
2
3 # BASH script to display RANDOM QUOTE and center text depending on terminal width.
4 # BASH script and quotations taken from CNET Amiga 2 AREXX PFILE
5 # AMIGA Version Copyright 1992 Jim Selleck and Beverly James Products
6 #
7 # BASH Script (C)24MAY2015 by Brent Hendricks
8 # Script and accompaning BLOG article (C) 2015 Brent Hendricks
9 # Script and quotes are public domain, the accompaning BLOG may only be used with permission
10 # Contact brent.hendricks@catracing.org if you wish to republish the article.
11 # Please visit Brent’s World @ www.catracing.org\hendrb
12
13 ## Get Terminal Width
14 TERMWIDE=”$(tput cols)”
15 ((TERMWIDE = TERMWIDE -3))
16
17 ## Set file path
18 QUOTATIONS=/home/local_hendrb01/dev/bash/randquote/quotations
19 TEMP_QUOTATION=/home/local_hendrb01/dev/bash/randquote/temp_quotation
20
21 ## Get number of quotations
22 QUOTES=”$(cat $QUOTATIONS | wc -l)”
23 ((QUOTES = QUOTES / 5))
24
25 ## Pick a record
26
27 RECORD=$(($RANDOM % $QUOTES * 5))
28
29 ## Read Quote from Quote file
30 sed -n “${RECORD},+5p” $QUOTATIONS > $TEMP_QUOTATION
31 sed -e :a -e “s/^.\{1,${TERMWIDE}\}$/ &/;ta” -e ‘s/\( *\)\1/\1/’ $TEMP_QUOTATION
32
33 ## Remove TEMP_QUOTATION scratch file
34 rm -f “${TEMP_QUOTATION}”

NOTE: Once you download the quotation file, you will need to rename it quotations, or change the quotations path to reflect the .txt extension (WordPress does not allow the uploading of files without extensions.)

We should by now know what line 1 does, and why we put it there, but as a quick reminder, Line 1 tells *NIX which interpreter to use. Just in case the user is in, or defaults to a different shell. Additionally AT&T used to default to the Bourne Shell, while BSD defaulted to the C shell.

While not needed if you never use a different shell, it is good practice, and insures compatibility.

Lines 3 – 11 are my standard comments, comments in shell scripts are preceded by #s

Lines 14 Gets the terminal width, and line 15 subtracts 3 from it. This is for the center justification routines later in the script.

Lines 18 and 19 set our file paths.
Line 18 is the path of the actual quotation file.
Line 19 is the path of the temp file created by SED

Lines 22 and 23 gets the number of quotations from the quotations file and puts them in the variable QUOTES. Note that our script is a bit different because we use the wc command to dynamically derive the number of quotes, as long as you remember that each quote uses 5 lines. This is done with the QUOTES=”$(cat $QUOTATIONS | wc -l)” command. Note the use and format here of command substitution. I am going to get nailed here by someone much smarter with BASH scripts than I am. For the wasteful use of the cat command, when technically you could have used just the wc –l and the file name. If done this way, the output was would have been ‘500 quotations’. To save time with a filtering statement, I just had the file cat’d, and piped through wc. The value is held in the variable QUOTES, then divided by 5. Since each 5 lines is a quote.

Line 27 Picks a random quote, in steps of 5. Since it would not do us much good to start reading in the middle of quote now would it?

Lines 30 and 31 are where the real magic occur, and what took me the longest to figure out. I could read various quotes all day until the sun came home, but while BASH has a command to left and right justify, it will not center justify. Again my method and someone else’s methods might vary. I could very well have loaded the quotations file in nano, or word and center justified it and re saved it. However that defeats the purpose of learning, defeats the purpose of making your quotation file dynamic, as each time you added a quote you would have to remember to justify it. It might also look funny if someone had a different sized terminal window then you did when you justified it.

Line 30 reads the 5 lines from the quotations file, and saves it in a file called temp_quotation.
Line 31 uses sed to center justify the text in the temp file and display it to the screen. The use of SED is outside the scope of this blog, and many good descriptions are available elsewhere on the net. If you are interested in the working of stream editor. I would start here. http://www.grymoire.com/Unix/Sed.html

Line 34 simply deletes the temp file, without prompting.

There you have it! A random quote generator for *NIX!

If we want this to be just like a BBS, and display it when a user logs in, we now have several choices to make.

Do we want this script to be run only when we login, or for all users?

If you want it displayed for all users, we must first move it somewhere where they have access to execute it. For this demonstration let’s move it to the /opt volume.

We can use the mv (MOVE) command.

sudo mv ./randqutoe /opt

I have to use sudo here, because root is the owner of the opt directory, and I do not have my local username added to the root group.

Once it is moved, I can verify the entire contests of the randquote directory were copied.

If I cd to /opt/randquote, I should have two files.

-rw-rw-r--. 1 local_hendrb01 local_hendrb01 9893 May 24 07:30 quotations
-rwxrwxr-x. 1 local_hendrb01 local_hendrb01 1169 May 30 13:22 randquote.sh

Make sure the file permissions match.

The next decision is if you want the randquote script to run only when you login to the console, or both the console and the terminal.

If you want it to execute when logging a console only,

Edit the following file in your favorite editor.
/etc/profile

And the following lines.

##Display Random Quote On Login For All Users Console Login ONLY
## Added by Your Name / DATE
echo
/opt/randquote/randquote.sh
echo

Save the file.
We must now edit the following lines in our randquote program, since it is no longer residing in your standalone development directory.

Change line 18 to read:
QUOTATIONS=/opt/randquote/quotations

Change line 19 to read:
TEMP_QUOTATION=/opt/temp_quotation
Save the file, now logoff then back on and you should now the random quote generated.

If you also wish a random quote to be generated when you launch a shell from a terminal window in XWindows or from the console.

NOTE: If you put in both files, you will have 2 quotes generated when logging in from the console!

We must do the following.

Using your favorite editor, add the following lines to /etc/bashrc

##Display Random Quote when opening a shell session via the terminal For All Users
## Added by Your Name / DATE
echo
/opt/randquote/randquote.sh
echo

Save the file.

Open a terminal session.

If you only want specific users to have the random quotes displayed.

edit their respective .profile and .bashrc files in their home directory /home/<shortname>/

For our next tutorial we are going to do three things with this script!

1) Add it to a LINUX login profile, for both terminal and console login
2) Add it to a OS X login profile, for both terminal and SSH login
3) We are going to add something magical for our OS X users!

So be sure to come back for next month’s technical blog, as we do more with *NIX!

Special thanks go to Ken Pletzer and Jim Selleck for the wonderful work you did in the 90s with C-Net Amiga Professional BBS. For the many hours of fun I had with your product!

Making Your OS X Terminal Look And Feel More Like Linux

If you are a Mac OS X power user who has spent any time in the terminal, and also used Linux. You will know firsthand that the OS X terminal can look kind of, well dull by comparison. One of the first things that you will notice is missing is the colorized directories, colorized grep output, as well as some of the directory listing shortcuts such as ‘ll’, and ‘l.’

Linux ll command

In this article we will explore how to modify your OS X terminal experience to match what you are used to seeing when using Linux.

First let’s take a look at the expanded List Directory Contents ‘ls’ command functionality in Linux.

We all know that to list the contents of a directory, in both Unix and Linux you use the ‘ls’ command. We can specify additional options on the command line. Like this

-a displays all files, including hidden files.
-l displays a long directory listing, displaying more information such as POSIX permissions, owner, group and file size information
-h displays “human readable” file sizes in a long listing.

These options can be combined in a single command, so typing ‘ls –lah’ will display a long listing, displaying all files, with “human readable” file sizes.

As mentioned above, most Linux distributions (RHL/CentOS, and Ubuntu), allow you to use the ls command to display a short list, ll to display the long list. Without specifying any options.

How is this done? How can I add the same functionality to my OS X terminal session?

In actuality it is quite easy, and done the same in OS X as it is done in Linux (Linux just happens to already have it in your login script.). It is done using the alias comman.

Alias allows you to set up alias’s for any command, with options, and use the normal command name, or you can choose a different name.
If you have access to a Linux box, open up a terminal windows and type ‘alias’ at a shell prompt. On CentOS 7, you will see the following output.

$ alias
alias egrep=’egrep --color=auto’
alias fgrep=’fgrep --color=auto’
alias grep=’grep --color=auto’
alias l.=’ls -d .* --color=auto’
alias ll=’ls -l --color=auto’
alias ls=’ls --color=auto’
alias which=’alias | /usr/bin/which --tty-only --read-alias --show-dot --show-tilde’

As you can see, in Linux when you use the ls command, it is not just ‘ls’ that is being executed but ls with the –color=auto option <colorizing OS X listing is done differently> which we will cover in the second part of this blog. Stay focused on the alias command for now.

Let’s add the l. and ll functionality right now.

The alias command is pretty straight forward.
Alias <COMMAND>=‘command string’

If you do not still have your OS X terminal window open, please open it again now.

At the command prompt type.
alias l.=’ls –d *’ <Hit Enter>
alias ll=’ls –l’ <Hit Enter>

Now let’s verify that it took your alias entries.
At the command prompt type alias

If the system accepted the alias’s you should now be able to do the following in your shell environment.

l. – Will display only directories in your current working directory
ll – Will display a long listing.

Here is the ll alias working.

Go ahead and test the functionality, while also play around with some of the other options. If you type ll –h for instance, you will see a long directory listing with the filesizes presented in “Human Readable Form” one of the great things about the BASH shell, is that you still have full command substitution available within an alias.
Part II – I also made reference to the ability to colorize the OS X directory listings. This is also done within the alias command, however it is done a bit differently.

OS X uses the –G option in the ls command to output the listing in color.

Here is the color ls output.

So let’s add some color to the standard ‘ls’ command

At your shell prompt type,

Alias ls=’ls –G’ <ENTER>

Type alias and <ENTER> to make sure your alias has been entered into the system.

Now let’s go back and add color to the other alias’s we created.

We can simply use command history to go back to the previous commands we have entered. Keep pressing your up cursor key until you see ‘alias ll=’ls –l’. Then use your left cursor key to move your cursor to the right of the single ‘ quote. Simply add the dash – and capital G and hit <ENTER>.

Now if you type the alias command by itself at your shell prompt you should see the modified ll alias.

Let’s try it out by typing ll at your shell prompt.

Here is the ll alias working.

Use command history and go back and add – and capital G to the l. command.
Use the alias command by itself to make sure it took
Test the l. alias.

Very good! You now have color directory listings in your OS X terminal environment.
Part III – Making these changes permanent.

Now that we have made the OS X terminal environment a little more colorful for your everyday use, and made it a perform more like the Linux systems you have been using there is one catch.

These changes are not yet permanent, in fact if we simply closed down our terminal window right now all our aliases would be lost! We do not even need to reboot or shut down our system!

So how do we make these changes stick?

There are a few files we need to modify, and depending on if you want it to apply to only a single user (Your account), or to any account that is on the system and opens a terminal shell or might ssh remotely to the computer.

If you only want the alias’s to be assigned to your shell environment, you need to add your alias commands to the ~\.bash_profile.

NOTE: ~\ is shorthand for YOUR home directory. So ~\.bash_profileis actually located in /Users/<shortname>

So let’s add the alias commands to the .bash_profile file

At your shell prompt enter alias
Select the output of the alias command
Copy the output

Now type nano ~\.bash_profile
Move the cursor to the bottom of any entries already in the file.
Paste your text in the file
Enter CTRL-X
Answer YES to save changes
Hit <Enter> to keep the same filename

Test functionality by typing exit then closing and reopening the terminal window.

Type alias, and you should see that the aliases you added are still there.

If you want to assign the alias’s to all users on the system, then add the above lines to the \etc\profile file.
PART IV – Modifying shell color output

You can specify how to color the specific componate in an ls output by using the LSICOLORS= option in your login script.

Adding LSICOLORS=<COLOR Colorcode> will modify the colors used for outputting the 11 functions.
The default value is, ‘exfxcxdxfxegedabagcad’

I have created this chart for ease of use.

Best practice calls for placing the line CLICOLOR=1 and LSCOLORS=exfxcxdxfxegedabagcad into your login script, but this is not necessary.

There you have it!  thanks for reading another Brent’s World OS X terminal / Linux blog!  We hope that you enjoyed learning a little more about your system!  Please remember, while using alias’s or system customization to make your system easier to use.  These modifications will not be available on other system, so practice the original functionality.