####  connect to your csci235 directory
cd ~/csci235

####  using your favorite text editor, create a C file containing the following code
####  I'll call my file funlab.c

#include <stdio.h>
#include <stdlib.h>

int main(int argc, char *argv[]) {
  for (int i=0; i<argc; ++i) {
    printf("arg %3d is %s\n", i, argv[i]) ;
  }
  return 0 ;
}

#### Compile the C program using the instructor flavored options

$$$$ gcc -std=c99 -Wpedantic -g -Og -o funlab funlab.c

#### Run it

$$$$  ./funlab do re mi fa sol la ti do

#### Typing that particular gcc every time will get tedious.
#### The bash shell allows you to create functions!

#### Pay attention..... you have to type TAB at one point

$$$$ cut --fields=1
.... hello are your paying attention
.... The tab	please
.... ^D
$$$$ cut --fields=1 --delimiter=: 
.... hello are your paying attention
.... The colon:please
.... ^D
$$$$ cut --fields=1 --delimiter=.
.... funlab.c
.... ^D
$$$$ echo funlab.c | cut --fields=1 --delimiter=.
$$$$ PREFIX=`echo ugh.c | cut --fields=1 --delimiter=.`
$$$$ echo $PREFIX

#### You can define functions in the Bash Shell!  Type carefully
$$$$ function c235 {
>>>>     MYFILE=`echo $1 | cut --fields=1 --delimiter=.`
>>>>     echo gcc -std=c99 -Wpedantic -o $MYFILE $1
>>>>     gcc -std=c99 -Wpedantic -o $MYFILE $1
>>>> }

#### Try it out!

$$$$ c235 funlab.c
$$$$ ls -lt funlab
$$$$ funlab

#### but.... How to you make this last!
$$$$ echo $PATH

#### You should see your bin directory!
#### Create a file /home/YOURID/bin/c235 with the following contents

#! /bin/bash 
PREFIX=`echo $1 | cut --fields=1 --delimiter=.`
echo RUNNING: gcc -std=c99 -Wpedantic -o $PREFIX $1
gcc -std=c99 -Wpedantic -o $PREFIX $1

#### Make sure it is executable
$$$$ chmod a+x ~/bin/c235
$$$$ ls -l ~/bin/c235

#### Be sure the shell can find it! And then try it out
$$$$ c235 funlab.c
$$$$ funlab


#### Try to compile your program with the defaults!
$$$$ gcc funlab.c

#### Make the changes shown in the following diff and recompile

5c5
<   for (int i=0; i<argc; ++i) {
---
>   for (int i=0; i<100; ++i) {

#### Run it...  This will not go well



#### Type the command "env" to see where these values came from
$$$$ env

#### Modify your program to print the pointer not its value. Here's a diff
6c6
<     printf("arg %3d is %s\n", i, argv[i]) ;
---
>     printf("arg %3d is %d\n", i, argv[i]) ;

#### You get a "pedantic" error.  Go ahead and run it!

#### Let's get rid of the 100. Go back to argc.
#### Take a *long* look at the man page for fprintf. The reference to a pointer!
#### Change the format to print argv[i] as a pointer.  (Use %p.)



#### Ugh -- hex... Try %d.

#### Ugh -- Try to cast argv[i] to (int)

#### Ugh -- Try to cast argv[i] to (void *)   -- that is the "generic" pointer

#### Ugh -- Try to cast argv[i] to (void *) to (int), that is (int)(void *)

#### Ugh -- Different sizes... Change the (int) to (long)

#### Ugh -- Change format specifier to %ld

#### Wait...  I liked the HEX better than that.  Go to %lx.

#### But it's 64 bits... that's 4*16.  Try %16lx .

#### ALL CAPS would look better.  Try %16lX

#### Let's have some leading zero's. That's %016lX 

#### Let's add the string back in.  The output should be something like:
arg   0 is at 00007FFCD9248D59 and is ./funlab
arg   1 is at 00007FFCD9248D62 and is do
arg   2 is at 00007FFCD9248D65 and is me
arg   3 is at 00007FFCD9248D68 and is ri