记录执行gdb的过程

#include <stdio.h>
#include <wchar.h>

int main(void)
{
        char str1[] = "abcd";
        wchar_t str2[] = L"abcd";

        return 0;
}

技巧

用gdb调试程序时，可以使用“set logging on”命令把执行gdb的过程记录下来，方便以后自己参考或是别人帮忙分析。默认的日志文件是“gdb.txt”，也可以用“set logging file file”改成别的名字。以上面程序为例：

(gdb) set logging file log.txt
(gdb) set logging on
Copying output to log.txt.
(gdb) start
Temporary breakpoint 1 at 0x8050abe: file a.c, line 6.
Starting program: /data1/nan/a 
[Thread debugging using libthread_db enabled]
[New Thread 1 (LWP 1)]
[Switching to Thread 1 (LWP 1)]

Temporary breakpoint 1, main () at a.c:6
6               char str1[] = "abcd";
(gdb) n
7               wchar_t str2[] = L"abcd";
(gdb) x/s str1
0x804779f:      "abcd"
(gdb) n       
9               return 0;
(gdb) x/ws str2
0x8047788:      U"abcd"
(gdb) q
A debugging session is active.

        Inferior 1 [process 9931    ] will be killed.

Quit anyway? (y or n) y

执行完后，查看log.txt文件：

bash-3.2# cat log.txt 
Temporary breakpoint 1 at 0x8050abe: file a.c, line 6.
Starting program: /data1/nan/a 
[Thread debugging using libthread_db enabled]
[New Thread 1 (LWP 1)]
[Switching to Thread 1 (LWP 1)]

Temporary breakpoint 1, main () at a.c:6
6               char str1[] = "abcd";
7               wchar_t str2[] = L"abcd";
0x804779f:      "abcd"
9               return 0;
0x8047788:      U"abcd"
A debugging session is active.

        Inferior 1 [process 9931    ] will be killed.

Quit anyway? (y or n)

可以看到log.txt详细地记录了gdb的执行过程。

此外“set logging overwrite on”命令可以让输出覆盖之前的日志文件；而 “set logging redirect on”命令会让gdb的日志不会打印在终端。
参见 gdb手册.