Using GDB to debug C program

#include <stdio.h>static void display (int i, int *ptr); int main (void) {   int x = 5;   int *xptr = &x;   printf ("in Main (): \ n");   printf ("   x is%d and was stored at%p.\n", X, &x);   printf ("   xptr points to%p which holds%d.\n", xptr, *xptr);   Display (x, xptr);   return 0;} void display (int z, int *zptr) {   printf ("in display (): \ n");   printf ("   Z is%d and was stored at%p.\n", Z, &z);   printf ("   zptr points to%p which holds%d.\n", zptr, *zptr);}

Use the file above, such as test.c

1, compile. Gcc-g-O testx test.c

2, run. GDB TESTX

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Reading symbols from Testx...done.
(GDB)

3, set the breakpoint. Gdb> B 8

Breakpoint 1 at 0x8048472:file test.c, line 8.

4, set breakpoint 2. Gdb> B 10

Breakpoint 2 at 0x80484ac:file test.c, line 10.

5, execute. Gdb> Run

Starting program:/HOME/WANG/MYTEST/GDBTEST/TESTX
In Main ():


Breakpoint 1, Main () at Test.c:8
8 printf ("X is%d and was stored at%p.\n", X, &x);

6, continue. Gdb> C

Continuing.
X is 5 and was stored at 0xbfffeb58.
Xptr points to 0xbfffeb58 which holds 5.


Breakpoint 2, Main () at Test.c:10
Ten display (x, xptr);

7, continue. Gdb> C

Continuing.
In Display ():
Z is 5 and was stored at 0XBFFFEB40.
Zptr points to 0xbfffeb58 which holds 5.
[Inferior 1 (process 11616) exited normally]

9, for step, using step

For BackTrace, using BT

Copyright NOTICE: This article for Bo Master original article, without Bo Master permission not reproduced.

Using GDB to debug C program