在 UBUNTU 下调试程序出现段错误（核心已转储）如何解决

[moxiaotiao]

在UBUNTU下运行程序

root@root-F81Se:$ flowcalc /trace/20010316.pcap.gz -e basic

直接出现

Opening trace file: Unable to guess format (/trace/20010316.pcap.gz)
flowcalc.c:279 main(): Reading file '/trace/20010316.pcap.gz' failed

已放弃 (核心已转储)

如何解决

[way2exluren]

……上代码…
把系统最好设置成英文…调试信息更好懂

[moxiaotiao]

@way2exluren
root@root-F81Se:~/下载/flowcalc$ flowcalc /trace/20010316.pcap.gz -e basic
%% flowcalc run at Sun Mar 1 10:43:47 2015
% modules: basic

@relation '/trace/20010316.pcap.gz'

%% flowcalc 0.1
% fc_id: flow id
% fc_tstamp: timestamp of first packet in the flow
% fc_duration: flow duration
% fc_proto: transport protocol
% fc_src_addr: IP address of connection initiator
% fc_src_port: TP port number of connection initiator
% fc_dst_addr: IP address of remote peer
% fc_dst_port: TP port number of remote peer
@attribute fc_id numeric
@attribute fc_tstamp numeric
@attribute fc_duration numeric
@attribute fc_proto {TCP,UDP}
@attribute fc_src_addr string
@attribute fc_src_port numeric
@attribute fc_dst_addr string
@attribute fc_dst_port numeric

%% basic_stats 0.1
% bs_min_size_up: minimum payload size in forward direction
% bs_avg_size_up: average payload size in forward direction
% bs_max_size_up: maximum payload size in forward direction
% bs_std_size_up: standard deviation of payload size in forward direction
% bs_min_size_down: minimum payload size in backward direction
% bs_avg_size_down: average payload size in backward direction
% bs_max_size_down: maximum payload size in backward direction
% bs_std_size_down: standard deviation of payload size in backward direction
% bs_min_iat_up: minimum inter-arrival time in forward direction
% bs_avg_iat_up: average inter-arrival time in forward direction
% bs_max_iat_up: maximum inter-arrival time in forward direction
% bs_std_iat_up: standard deviation of inter-arrival time in forward direction
% bs_min_iat_down: minimum inter-arrival time in backward direction
% bs_avg_iat_down: average inter-arrival time in backward direction
% bs_max_iat_down: maximum inter-arrival time in backward direction
% bs_std_iat_down: standard deviation of inter-arrival time in backward direction
@attribute bs_min_size_up numeric
@attribute bs_avg_size_up numeric
@attribute bs_max_size_up numeric
@attribute bs_std_size_up numeric
@attribute bs_min_size_down numeric
@attribute bs_avg_size_down numeric
@attribute bs_max_size_down numeric
@attribute bs_std_size_down numeric
@attribute bs_min_iat_up numeric
@attribute bs_avg_iat_up numeric
@attribute bs_max_iat_up numeric
@attribute bs_std_iat_up numeric
@attribute bs_min_iat_down numeric
@attribute bs_avg_iat_down numeric
@attribute bs_max_iat_down numeric
@attribute bs_std_iat_down numeric

@data
Opening trace file: Unable to guess format (/trace/20010316.pcap.gz)
flowcalc.c:279 main(): Reading file '/trace/20010316.pcap.gz' failed

已放弃 (核心已转储)

[halczy]

可能是中文目录名的问题。移到一个纯英文的目录再试下。

[way2exluren]

我还以为是自己写代码报错…原来是程序运行…
提示信息是文件错误啊……格式问题…

[9hills]

core dump ，用gdb 看core呗

[moxiaotiao]

@way2exluren 是的，装了一个程序，读取的数据格式没问题，从官网下载的

[moxiaotiao]

@9hills

GDB RESULT:

warning: Can't read pathname for load map: 输入/输出错误.
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/i386-linux-gnu/libthread_db.so.1".
Core was generated by `flowcalc /home/maopengxin/trace/20010316.pcap.gz -e basic'.
Program terminated with signal 6, Aborted.
#0 0xb76fc424 in __kernel_vsyscall ()
gdb()

[9hills]

@moxiaotiao 用bt看断点，然后看看变量

[moxiaotiao]

@9hills

(gdb) bt
#0 0xb76fc424 in __kernel_vsyscall ()
#1 0xb75521df in raise () from /lib/i386-linux-gnu/libc.so.6
#2 0xb7555825 in abort () from /lib/i386-linux-gnu/libc.so.6
#3 0xb76d7260 in _die (file=0x8049d1e "flowcalc.c", line=279,
fn=0x804a2e9 "main", msg=0x804a2cf "Reading file '%s' failed\n")
at lib.c:126
#4 0x080497a0 in main ()

[9hills]

#3 0xb76d7260 in _die (file=0x8049d1e "flowcalc.c", line=279,
fn=0x804a2e9 "main", msg=0x804a2cf "Reading file '%s' failed\n")
at lib.c:126

上面不是写了么，断点在 flowcalc.c的279行，先去看看行内是什么，然后print下相关变量debug

[moxiaotiao]

你好，279行的代码就是下面这个

if (!lfc_run(fc->lfc, fc->file, fc->filter))
die("Reading file '%s' failed\n", fc->file);

[moxiaotiao]

@9hills

你好，279行的代码就是下面这个

if (!lfc_run(fc->lfc, fc->file, fc->filter))
die("Reading file '%s' failed\n", fc->file);

你意思是GDB下面Print？

[9hills]

@moxiaotiao 是的，你先学习下 gdb 的简单使用吧，很快的。然后结合代码 debug 即可

[marguerite]

最难的就是转储核心啦，你都有转储得核心就很简单了啊：

gdb
core 你的转储文件
bt

没有调试符号就按提示装调试符号，xxx-debuginfo 什么的重跑上面步骤就可以了。