==== Running it =======

mahoney@cs test_bytes$ make test_bytes
gcc -std=c99 -march=athlon64 -O2    test_bytes.c   -o test_bytes
mahoney@cs test_bytes$ ./test_bytes
Using little_endian: This machine is Little-Endian
Using big_endian: This machine is Little-Endian
(int) 12345
 0x   39 30 00 00
(long) 12345
 0x   39 30 00 00
(short) 12345
 0x   39 30
(float) 12345
 0x   00 e4 40 46
(double) 12345
 0x   00 00 00 00 80 1c c8 40
&ival
 0x   4c a2 fe bf
mahoney@cs test_bytes$ 

==== Looking at the stack with gdb =====

   == (very) short list of some gdb commands ==
   start
   run
   l addr        list, by default shows 10 lines, optional address
   b addr        set breakpoint, e.g. "break main" or "break 10"
   p variable    print, e.g. "p &x"
   x/16xb addr   examine memory, 16 of hex bytes, e.g. "x/16xb &x"
   s             step forward one line
   help
   set variable=value
 
# Compile with debugging symbols
$ mahoney@cs test_bytes$ gcc -g test_bytes.c -o test_bytes  # gdb symbols
$ mahoney@cs test_bytes$ gdb 
(gdb) start
Temporary breakpoint 1 at 0x8048721: file test_bytes.c, line 92.
92	  int val = 12345;
(gdb) l
87	  printf("&ival\n");
88	  show_pointer(pval);
89	}
90	
91	int main(int argc, char *argv[]) {
92	  int val = 12345;
93	
94	  if (argc > 1)
95	    sscanf(argv[1], "%d", &val);
96	  test(val);
(gdb) p val
-1208193036
(gdb) s
94	  if (argc > 1)
(gdb) p val
$2 = 12345
(gdb) p &val
$3 = (int *) 0xbffff82c
(gdb) p (char) val
$4 = 57 '9'
(gdb) x/16xb &val
0xbffff82c:     0x39    0x30    0x00    0x00    0x80    0x87    0x04    0x08
0xbffff834:     0x00    0x00    0x00    0x00    0xb8    0xf8    0xff    0xbf
(gdb) x/16ub &val
0xbffff82c:     57      48      0       0       128     135     4       8
0xbffff834:     0       0       0       0       184     248     255     191

... and so on