C :: Variable Memory Location With Ampersand Vs Pmap

Oct 23, 2014

I just started deal with pointers in C, and one stuff confusing me...

Here is simple code:

int main (){
int var1 = 10;
int var2 = 20;
long ms = 10000000;

printf("Address of var1 variable: %p
", &var1 );

[Code] ...

But - when I run pmap - I don't see this addresses there:

Code:
# pmap -x 16496
16496: ./address
Address Kbytes RSS Dirty Mode Mapping
0000000000400000 4 4 0 r-x-- address
0000000000600000 4 4 4 rw--- address
00007f79cf8b8000 1576 260 0 r-x-- libc-2.12.so
00007f79cfa42000 2048 0 0 ----- libc-2.12.so
00007f79cfc42000 16 16 16 r---- libc-2.12.so

I guess - it's is inside stack:

Code:
# cat /proc/16496/maps | grep stack
7fff0d7e5000-7fff0d7fa000 rw-p 00000000 00:00 0 [stack]

But - how I can obtain this variables addreses, to see them with `pmap`? If I put them as "global":

Code: ...
#include <stdlib.h>
#include <sys/types.h>
int var1 = 10;
int var2 = 20;
int millisleep(unsigned ms);
int retpid(void);

[Code] ......

I have odd addresses in result:

Code:
Address of var1 variable: 0x600a94
Address of var2 variable: 0x600a98

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[Code].....

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