(gdb) file bomb Reading symbols from bomb... (gdb) set args solutions.txt (gdb) r Starting program: /home/dominic/learning-linux/bomb/bomb solutions.txt Welcome to my fiendish little bomb. You have 6 phases with which to blow yourself up. Have a nice day! Phase 1 defused. How about the next one? That's number 2. Keep going!
(gdb) l 23 #include <stdio.h> 24 #include <stdlib.h> 25 #include "support.h" 26 #include "phases.h" 27 28 /* 29 * Note to self: Remember to erase this file so my victims will have no 30 * idea what is going on, and so they will all blow up in a 31 * spectaculary fiendish explosion. -- Dr. Evil 32 */ (gdb) l 33 34 FILE *infile; 35 36 int main(int argc, char *argv[]) 37 { 38 char *input; 39 40 /* Note to self: remember to port this bomb to Windows and put a 41 * fantastic GUI on it. */ 42
set list num设置默认显示代码行数
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(gdb) set list 20 //默认显示20行代码
list linenumber查看指定行代码
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(gdb) l 10 (gdb) l main.h : 10//指定main.c文件中的第十行
list function查看指定函数的代码
break 打断点
break linenum对指定行打断点
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(gdb) b 36 Note: breakpoint 1 also set at pc 0x400da0. Breakpoint 2 at 0x400da0: file bomb.c, line 37.
break function对指定函数打断点
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(gdb) b main Breakpoint 3 at 0x400da0: file bomb.c, line 37. (gdb) b phase_1 Breakpoint 4 at 0x400ee0
删除断点包括禁用断点
delete删除所有断点
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(gdb) delete Delete all breakpoints? (y or n) y
disable breakpoint禁用断点
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(gdb) info b #先看有哪些断点 Num Type Disp Enb Address What 3 breakpoint keep y 0x0000000000400da0 in main at bomb.c:37 4 breakpoint keep y 0x0000000000400ee0 <phase_1> (gdb) d 3 #禁用第三号断点 (gdb) info b #再次查看断点信息发现已经没有第三号断点 Num Type Disp Enb Address What 4 breakpoint keep y 0x0000000000400ee0 <phase_1>
clear function删除一个函数中所有的断点
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(gdb) info b Num Type Disp Enb Address What 4 breakpoint keep y 0x0000000000400ee0 <phase_1> (gdb) clear phase_1 (gdb) info b Deleted breakpoint 4 No breakpoints or watchpoints.
启动与退出
run启动程序直到遇到断点
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(gdb) run
start启动程序并在第一条代码处停下
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(gdb) start
x配置gdb常用命令
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$ gdb -q -x gdbinit
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//gdbinit display/z $xs display/z $x6 display/z $x7 set disassemble-next-line on b _start target remote: 34
有了配置文件，就不用每次启动gdb时都要重新输入一遍调试命令。
quit退出调试
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(gdb) quit
调试命令
print打印变量值
格式化字符 (/fmt)
说明
/x
以十六进制的形式打印出整数。
/d
以有符号、十进制的形式打印出整数。
/u
以无符号、十进制的形式打印出整数。
/o
以八进制的形式打印出整数。
/t
以二进制的形式打印出整数。
/f
以浮点数的形式打印变量或表达式的值。
/c
以字符形式打印变量或表达式的值。
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(gdb) p i # 10进制 $5 = 3 (gdb) p/x i # 16进制 $6 = 0x3 (gdb) p/o i # 8进制 $7 = 03
ptype打印变量类型
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(gdb) ptype i type = int (gdb) ptype array[i] type = int (gdb) ptype array type = int [12]
