/*
 * TEST CASE TO CHECK DIFFERENCES BETWEEN STRING AS
 * AN ARRAY OF CHARS AND AS A POINTER TO CHAR
 */

#include  <stdio.h>
//#include  <string.h>

int main(void)
{
	char a[] = "foo";
	char *b  = "bar";
	char * const c = "changeme";

	printf("a - %s %c %p\n", a, *a, a);
	printf("b - %s %c %p\n", b, *b, b);
	//printf("c - %s %c %p\n", c, *c, c);

	//c = "ok";   //compiler error
	//*c = 's';   //compiles, but segfaults when executing (why?)
	//c[1] = 't'; //compiles, but segfaults when executing (why?)
	
	b = "qwe"; //b lost previous address

	/*
	 * THESE DO NOT WORK
	 */
	//b[] = "zxc"; //compiler error
	//a = "dfg";   //compiler error
	//a[] = "rty"; //compiler error

	*a = "cvb"; //have no idea, what a hell it does (after xxd it seems it's writing MSB or LSB of &"cvb")

	printf("a - %s %c %p\n", a, *a, a);
	printf("b - %s %c %p\n", b, *b, b);
	
	/*
	 * THESE DO NOT WORK
	 */
	//b[0] = 't';  //compiles, but segfaults when executing (why?)
	//*b = 'b';    //compiles, but segfaults when executing (why?)

	b = a;

	printf("b - %s %c %p\n", b, *b, b);

	b[2] = 't';
	*(b+1) = 'b';
	*(++b) = 'n'; 
	--b;

	printf("b - %s %c %p\n", b, *b, b);

	a[0] = 'z';
	*(a+1) = 'e';
	//*(++a) = 'r'; //compiler error (expected)

	printf("b - %s %c %p\n", a, *a, a);

	return 0;
}

a - foo f 0xbff204b8
b - bar b 0x80485e0
a - 
oo 
 0xbff204b8
b - qwe q 0x8048609
b - 
oo 
 0xbff204b8
b - 
nt 
 0xbff204b8
b - zet z 0xbff204b8

char a[] = {'f', 'o', 'o'};

#include <stdio.h>

int main(int argc, char **argv) {
        char *s = "dragonforce";
        printf("Address(s)   = 0x%08X\n", &s);
        printf("Value(s)     = %s\n", s);
        s[7] = 'a';
        printf("New Value(s) = %s\n", s);
        return 0;
}

(gdb) break 7
Breakpoint 1 at 0x1c000722: file test.c, line 7.
(gdb) run
Starting program: /home/taylor/test 
Address(s)   = 0xCFBF015C
Value(s)     = dragonforce

Breakpoint 1, main (argc=1, argv=0xcfbf01dc) at test.c:7
7               s[7] = 'a';
(gdb) print &s[7]
$1 = 0x3c000008 "orce"
(gdb) cont
Continuing.

Program received signal SIGSEGV, Segmentation fault.
0x1c000728 in main (argc=1, argv=0xcfbf01dc) at test.c:7
7               s[7] = 'a';
(gdb) The program is running.  Exit anyway? (y or n) y

b[] = "zxc";  /* invalid syntax */
a = "dfg";    /* type mismatch, char * vs. char[] */
a[] = "rty";  /* invalid syntax */

        *a = "cvb"; //have no idea, what a hell it does (after xxd it seems it's writing MSB or LSB of &"cvb")
	 /*
	 * THESE DO NOT WORK
	 */
	//b[0] = 't';  //compiles, but segfaults when executing (why?)
	//*b = 'b';    //compiles, but segfaults when executing (why?)

	char a[] = "foo";

	char *b  = "bar";

	char * const c = "changeme";

c = "ok";   //compiler error

*c = 's';   //compiles, but segfaults when executing (why?)

c[1] = 't'; //compiles, but segfaults when executing (why?)

	b = "qwe"; //b lost previous address

b[] = "zxc"; //compiler error

a = "dfg";   //compiler error

int x=5;
int u=x;  // Can use x (an int variable) the way we might use a number
int v=7;  // Can use 7 (a number) as a number
x = 4;    // Can change an int variable to have a new value.
7 = 4;    // Cannot change a number to have a new value.

	char a[] = "foo";
	char *b  = "bar";
. . .
	b = a;
. . .
	b[2] = 't';