Memory distribution under Linux

Sunday tells the memory distribution under 32-bit Linux

and the use of extern and static in C language.

Up to 1 g of memory is used as a system reservation, followed by space, near the 3G

Then down is the heap space, followed by the BSS, uninitialized static variable area

And then the RW data area.

Ro data area, primarily used as a storage string type

Next is the code snippet, also known as TXT body segment

0xFFFFFFFF Kernel

0XBFFF FFFF Stack

Heap

BSS area

RW data

RO data

Code snippet 0x00000000

The next step is to verify

1#include <stdio.h>2 3 Static intSg_init =Ten;4 Static intSg_uninit;5 6 7 intMain ()8 {9 Ten     intL_init =Ten; One     Static intInit_stack =Ten; A     Static intUninit_stack; -     Static intUninit_xxx =0; -      theprintf"Sg_init%p\n",&sg_init); -printf"Sg_uninit%p\n",&sg_uninit); -printf"L_init%p\n",&l_init); -printf"Init_stack%p\n",&init_stack); +printf"Uninit_stack%p\n",&uninit_stack); -printf"String,ro Data%p\n","Hello"); +printf"function%p\n", main); A  at}

View Code

The operation results are as follows

Sg_init 0x804a014
Sg_uninit 0x804a024
L_init 0xbfa0718c
Init_stack 0x804a018
Uninit_stack 0x804a028
String,ro Data 0x80485da
function 0x80483e4

Visible local variables are stored in the stack space because they are relatively close to the heap space 0xbf

The uninitialized static global variable and the static local variable are next to each other, and are higher than the initialized position, so the model is validated

The rodata is lower than the Rwdata segment, indicating that the static zone model is also correct

Similarly, the address of the code snippet conforms to the above model.

There is a less rigorous proof that the local variable stack space, how to exclude it is not in the heap space? How big is the stack space?

I don't understand it yet.

Memory distribution under Linux