How can one see content of stack with GDB

Question

I am new to GDB  so I have some questions    How can I look at content of the stack  Example  to see content of register  I type info registers  For the stack  what should it be  How can I see the content of  0x4  esp   When I type print  d  0x4  esp   GDB gives an error    Platform  Linux and GDB

User · Answer

Use    bt - backtrace  show stack functions and args info frame - show stack start end args locals pointers  x 100x  sp - show stack memory    gdb  bt  0  zzz    at zzz c 96  1  0xf7d39cba in yyy  arg arg entry 0x0  at yyy c 542  2  0xf7d3a4f6 in yyyinit    at yyy c 590  3  0x0804ac0c in gnninit    at gnn c 374  4  main  argc 1  argv 0xffffd5e4  at gnn c 389   gdb  info frame Stack level 0  frame at 0xffeac770   eip   0x8049047 in main  goo c 291   saved eip 0xf7f1fea1  source language c   Arglist at 0xffeac768  args  argc 1  argv 0xffffd5e4  Locals at 0xffeac768  Previous frame s sp is 0xffeac770  Saved registers    ebx at 0xffeac75c  ebp at 0xffeac768  esi at 0xffeac760  edi at 0xffeac764  eip at 0xffeac76c   gdb  x 10x  sp 0xffeac63c  0xf7d39cba  0xf7d3c0d8  0xf7d3c21b  0x00000001 0xffeac64c  0xf78d133f  0xffeac6f4  0xf7a14450  0xffeac678 0xffeac65c  0x00000000  0xf7d3790e

User · Answer

You need to use gdb s memory-display commands  The basic one is x  for examine  There s an example on the linked-to page that uses  gdb gt  x 4xw  sp   to print  four words  w   of memory above the stack pointer  here   sp  in hexadecimal  x    The quotation is slightly paraphrased

User · Answer

info frame to show the stack frame info  To read the memory at given addresses you should take a look at x  x x  esp for hex x d  esp for signed x u  esp for unsigned etc  x uses the format syntax  you could also take a look at the current instruction via x i  eip etc

[c] How can one see content of stack with GDB?

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