2.68 在GDB中拼接字符串

https://scz.617.cn/unix/201612011200.txt

Q:

如何在GDB脚本中或GDB提示符下拼接字符串？

A: Craig Ringer 2016-12-01

Concatenate GDB convenience variables - [2016-12-01]
https://stackoverflow.com/questions/40917677/concatenate-gdb-convenience-variables

--------------------------------------------------------------------------
import gdb

class Concat ( gdb.Function ) :

    def __init__ ( self ) :
        super( Concat, self ).__init__( "concat" )

    def _unwrap_string ( self, v ) :
        try:
            return v.string()
        except gdb.error :
            return str( v )

    def invoke ( self, *args ) :
        return ''.join( [self._unwrap_string(x) for x in args] )

Concat()
--------------------------------------------------------------------------

(gdb) source concat.py
(gdb) set $x=$concat("works", " ", "when", " ", "detached")
(gdb) p $x
$1 =   "works when detached"

D: 付程 2021-05-28

define concat2
    set $ret=0
    set $ret=$arg0 $arg1
end
concat2 "aaa" "bbbb"
p $ret

"set $ret=0"的意图是"重置"，以此避免下一条set触发"Too many array elements"

参看:

https://github.com/basinilya/wisdom/blob/master/prog/gdb/gdb-faq.txt

GDB直接支持字符串拼接，擦，以前不知道可以这样写。这样的话，就不需要concat
函数或者define，原始需求GDB直接满足。

set $any=0
set $any="aaa" " " "bbbb" " " "ccccc"
p $any

输出"aaa bbbb ccccc"