Home/ Questions/Q 4056356
In Process

The Archive Base Latest Questions

Editorial Team
  • 0
Asked: 2026-05-20T14:49:01+00:00

In my code I tried to print the address of printf() function. 22834: ./a.out

  • 0

In my code I tried to print the address of printf() function. 

22834:   ./a.out
00250000   1372K r-x--  /lib/libc-2.12.1.so
003a7000      8K r----  /lib/libc-2.12.1.so
003a9000      4K rw---  /lib/libc-2.12.1.so
003aa000     12K rw---    [ anon ]
00a14000    112K r-x--  /lib/ld-2.12.1.so
00a30000      4K r----  /lib/ld-2.12.1.so
00a31000      4K rw---  /lib/ld-2.12.1.so
00fb9000      4K r-x--    [ anon ]
08048000      4K r-x--  /home/anirudh/Documents/DUMP/a.out
08049000      4K r----  /home/anirudh/Documents/DUMP/a.out
0804a000      4K rw---  /home/anirudh/Documents/DUMP/a.out
08068000    132K rw---    [ anon ]
b7898000      4K rw---    [ anon ]
b78ac000      8K rw---    [ anon ]
bfc9a000    132K rw---    [ stack ]
 total     1808K

Address of the function "printf()" in HEX = 8048408

I was expecting its address to be a part of

00250000 1372K r-x-- /lib/libc-2.12.1.so
rather than as shown that its code is in this section
08048000 4K r-x-- /home/anirudh/Documents/DUMP/a.out i.e code segment of my code.

I even tried printing the address of a few more functions like getpid() and scanf() but they were all shown to be part of my program’s code segment rather than the libc-2.12.1.so

What is the reason for this ?. Thanks in advance.

Share

Leave an answer

You must login to add an answer.

Need An Account,

1 Answer

  1. Editorial Team

    Look at the code that is at the printf address; it is probably just an indirect jump or call that calls into libc. Typically, calls to shared libraries are turned into references to a dispatch function that is patched with (or looks up) the actual address where printf was loaded. If you run readelf -a on your executable and look for the address where you found printf, it will probably be marked as a relocation to be pointed to the actual address in libc.

    • 0