gdb cheat sheet

0x01 控制流

r　　　　　　　　run，运行程序。

r < a.txt　　　　  run，重定向输入

si　　　  　　　　step instruction 进入函数

ni　　　  　　　   next instruction 下一条指令

finish　　　　　  执行到函数结束

0x02 断点

b　　　　　　　　block，下断点

b *0x0000xx　　   在指定位置下断点

b main　　　　     在函数入口下断点

watch *0x00xx　   当修改指定内存时中断

rwatch *0x00xx     当读取指定内存时中断

info b　　　　       查看当前断点

en 1 2 3　　　　   允许中断

dis 1 2 3　　　      不允许中断

0x03 内存

x

x [Address expression]
x /[Format] [Address expression]
x /[Length][Format] [Address expression]

Address expression

Specifies the memory address which contents will be displayed. This can be the address itself or any C/C++ expression evaluating to address. The expression can include registers (e.g. $eip) and pseudoregisters (e.g. $pc). If the address expression is not specified, the command will continue displaying memory contents from the address where the previous instance of this command has finished.

Format

If specified, allows overriding the output format used by the command. Valid format specifiers are:

• o - octal
• x - hexadecimal
• d - decimal
• u - unsigned decimal
• t - binary
• f - floating point
• a - address
• c - char
• s - string
• i - instruction

The following size modifiers are supported:

• b - byte
• h - halfword (16-bit value)
• w - word (32-bit value)
• g - giant word (64-bit value)

x /16xb 0x123123

x /s  0x123123123

---只会这么多了