#
# Examining a process address space
#

See the slide with a picture of a process address space on Solaris x86 32-bit.
Example outputs on Nevada x86 32-bit (~ OpenSolaris):

--- output 1 ---

janp:ananke:snv_102:~$ ./proc-addr-space 
local variable:         0x8047a64
noninitialized var:     0x8061504
initialized var 1:      0x8061134
initialized var 2:      0x8061138

=== pmap 11467 ===
11467:  ./proc-addr-space
08046000       8K rwx--    [ stack ]
08050000       4K r-x--  /export/home/janp/proc-addr-space
08060000       8K rwx--  /export/home/janp/proc-addr-space
CEA35000       4K rwxs-    [ anon ]
CEA40000      24K rwx--    [ anon ]
CEA50000    1280K r-x--  /usr/lib/libc/libc_hwcap1.so.1
CEB90000      32K rwx--  /usr/lib/libc/libc_hwcap1.so.1
CEB98000       8K rwx--  /usr/lib/libc/libc_hwcap1.so.1
CEBB0000       4K rwx--    [ anon ]
CEBBE000     184K r-x--  /lib/ld.so.1
CEBFC000       8K rwx--  /lib/ld.so.1
CEBFE000       4K rwx--  /lib/ld.so.1
 total      1568K

	- no heap since malloc() wasn't called at all
	- all global variables are part of the data segment

--- output 2 ---

janp:ananke:snv_102:~$ ./proc-addr-space 1
local variable:         0x8061518
noninitialized var:     0x8061504
initialized var 1:      0x8061134
initialized var 2:      0x8061138

=== pmap 11472 ===
11472:  ./proc-addr-space 1
08046000       8K rwx--    [ stack ]
08050000       4K r-x--  /export/home/janp/proc-addr-space
08060000       8K rwx--  /export/home/janp/proc-addr-space
08062000       8K rwx--    [ heap ]
CEA35000       4K rwxs-    [ anon ]
CEA40000      24K rwx--    [ anon ]
CEA50000    1280K r-x--  /usr/lib/libc/libc_hwcap1.so.1
CEB90000      32K rwx--  /usr/lib/libc/libc_hwcap1.so.1
CEB98000       8K rwx--  /usr/lib/libc/libc_hwcap1.so.1
CEBB0000       4K rwx--    [ anon ]
CEBBE000     184K r-x--  /lib/ld.so.1
CEBFC000       8K rwx--  /lib/ld.so.1
CEBFE000       4K rwx--  /lib/ld.so.1
 total      1576K

	- malloc() was called we we have a heap now
	- however, a local variable still point inside of the data segment since
	  there is some free space that malloc() can use
	- heap has 8KB which is the minimum for storing internal malloc()
	  structures for managing the memory

--- output 3 ---

janp:ananke:snv_102:~$ ./proc-addr-space 8192
local variable:         0x8061510
noninitialized var:     0x8061504
initialized var 1:      0x8061134
initialized var 2:      0x8061138

=== pmap 11480 ===
11480:  ./proc-addr-space 8192
08046000       8K rwx--    [ stack ]
08050000       4K r-x--  /export/home/janp/proc-addr-space
08060000       8K rwx--  /export/home/janp/proc-addr-space
08062000      16K rwx--    [ heap ]
CEA35000       4K rwxs-    [ anon ]
CEA40000      24K rwx--    [ anon ]
CEA50000    1280K r-x--  /usr/lib/libc/libc_hwcap1.so.1
CEB90000      32K rwx--  /usr/lib/libc/libc_hwcap1.so.1
CEB98000       8K rwx--  /usr/lib/libc/libc_hwcap1.so.1
CEBB0000       4K rwx--    [ anon ]
CEBBE000     184K r-x--  /lib/ld.so.1
CEBFC000       8K rwx--  /lib/ld.so.1
CEBFE000       4K rwx--  /lib/ld.so.1
 total      1584K

	- local variable still points to the data segment but we can see that
	  the heap is 16KB now which means that some of the memory was allocated
	  already from the heap.