#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 is 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 is stored at %p.\n", z, &z);
printf(" zptr points to %p which holds %d.\n", zptr, *zptr);
}
使用上面的file， 比方 test.c
1, 编译。 gcc -g -o testx test.c
2, 执行。 gdb testx
GNU gdb (Ubuntu 7.7.1-0ubuntu5~14.04.2) 7.7.1
Copyright (C) 2014 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
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There is NO WARRANTY, to the extent permitted by law. Type "show copying"
and "show warranty" for details.
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Type "show configuration" for configuration details.
For bug reporting instructions, please see:
<http://www.gnu.org/software/gdb/bugs/>.
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<http://www.gnu.org/software/gdb/documentation/>.
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Type "apropos word" to search for commands related to "word"...
Reading symbols from testx...done.
(gdb)
3, 设置断点。 gdb> b 8
Breakpoint 1 at 0x8048472: file test.c, line 8.
4, 设置断点2。 gdb> b 10
Breakpoint 2 at 0x80484ac: file test.c, line 10.
5, 运行。
gdb> run
Starting program: /home/wang/mytest/gdbtest/testx
In main():
Breakpoint 1, main () at test.c:8
8 printf(" x is %d and is stored at %p.\n", x, &x);
6, 继续。 gdb> c
Continuing.
x is 5 and is stored at 0xbfffeb58.
xptr points to 0xbfffeb58 which holds 5.
Breakpoint 2, main () at test.c:10
10 display(x, xptr);
7, 继续。 gdb> c
Continuing.
In display():
z is 5 and is stored at 0xbfffeb40.
zptr points to 0xbfffeb58 which holds 5.
[Inferior 1 (process 11616) exited normally]
9, for step, using step
10, for backtrace, using bt
