//-I意为include 指定头文件搜索路径 -l:告诉编译器链接时需要的库
gcc *.c -I /usr/include/fastdfs/ -I /usr/include/fastcommon/ -l fdfsclient//调试gcc -g -rdynamic main.c
如何解决 “ 段错误(吐核) ” ???
【线上排错】记一次Linux的“段错误(吐核)”排查步骤
Centos 开始Core调试
[Linux] 什么是 段错误(吐核)?
Linux环境下段错误的产生原因及调试方法小结
跟着视频操作,运行代码出现
[fish@localhost mytest]$ ./a.out
段错误(吐核)
参考了上述连接不断调试,并且反复校对代码和视频以及资料中的差别,无果
最后得到的调试信息是
(gdb) run
Starting program: /home/fish/mytest/./a.out
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib64/libthread_db.so.1".Program received signal SIGSEGV, Segmentation fault.
0x00007ffff7874a4a in __GI__IO_str_overflow (fp=0x7fffffffd2c0, c=91) at strops.c:133
133 *fp->_IO_write_ptr++ = (unsigned char) c;
个人感觉是哪个地方的读写出了问题,导致内存访问溢出了之类的,但是没找到具体是哪个语句的调用出了问题。先记一下,后续有时间再调。要是有知道哪儿出问题的大佬,请不吝赐教!
对应调用出错位置代码:
(gdb) l
128 fp->_IO_write_end = fp->_IO_buf_end;
129 }
130 }
131
132 if (!flush_only)
133 *fp->_IO_write_ptr++ = (unsigned char) c;
134 if (fp->_IO_write_ptr > fp->_IO_read_end)
135 fp->_IO_read_end = fp->_IO_write_ptr;
136 return c;
137 }
(gdb) l
138 libc_hidden_def (_IO_str_overflow)
139
140 int
141 _IO_str_underflow (_IO_FILE *fp)
142 {
143 if (fp->_IO_write_ptr > fp->_IO_read_end)
144 fp->_IO_read_end = fp->_IO_write_ptr;
145 if ((fp->_flags & _IO_TIED_PUT_GET) && (fp->_flags & _IO_CURRENTLY_PUTTING))
146 {
147 fp->_flags &= ~_IO_CURRENTLY_PUTTING;
贴下源码:
main.c
#include <stdio.h>
#include <unistd.h>
#include <pthread.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <string.h>
#include "fdfs_upload_file.h"int main(int argc,const char* argv[]){char fileID[1024] = {0};upload_file1("/etc/fdfs/client.conf","main.c",fileID);printf("fileID:%s\n",fileID);printf("==================\n");upload_file2("/etc/fdfs/client.conf","main.c",fileID,sizeof(fileID));printf("fileID:%s\n",fileID);return 0;
}
fdfs_upload_file.h
#ifndef _FDFS_UPLOAD_FILE_H
#define _FDFS_UPLOAD_FILE_Hint upload_file1(const char* confFile, const char* localFile, char* fileID);
int upload_file2(const char* confFile, const char* localFile, char* fileID, int bufLen);#endif
fdfs_upload_file.c
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <sys/wait.h>
#include "fdfs_client.h"
#include "fdfs_upload_file.h"int upload_file1(const char* confFile,const char* localFile,char* fileID)
{char group_name[FDFS_GROUP_NAME_MAX_LEN + 1];ConnectionInfo *pTrackerServer;int result;int store_path_index;ConnectionInfo storageServer;if ((result=fdfs_client_init(confFile)) != 0){return result;}pTrackerServer = tracker_get_connection();if (pTrackerServer == NULL){fdfs_client_destroy();return errno != 0 ? errno : ECONNREFUSED;}*group_name = '\0';if ((result=tracker_query_storage_store(pTrackerServer, \&storageServer, group_name, &store_path_index)) != 0){fdfs_client_destroy();fprintf(stderr, "tracker_query_storage fail, " \"error no: %d, error info: %s\n", \result, STRERROR(result));return result;}result = storage_upload_by_filename1(pTrackerServer, \&storageServer, store_path_index, \localFile, NULL, \NULL, 0, group_name, fileID);if (result == 0){printf("%s\n", fileID);}else{fprintf(stderr, "upload file fail, " \"error no: %d, error info: %s\n", \result, STRERROR(result));}tracker_disconnect_server_ex(pTrackerServer, true);fdfs_client_destroy();return result;
}//多进程实现
int upload_file2(const char* confFile,const char* localFile,char* fileID,int bufLen){//创建管道int fd[2];int ret=pipe(fd);if(ret==-1){perror("pipe reeor");exit(0);}//创建子进程pid_t pid = fork();//如果是子进程if(pid==0){//3.标准输出重定向 -》管道的写端dup2(fd[1],STDOUT_FILENO);//4.关闭读端close(fd[0]);//5。执行execlp命令execlp("fdfs_upload_file","xxx",confFile, localFile, NULL);perror("execlp error");}else{//父进程,读管道//关闭写端close(fd[1]);read(fd[0],fileID,bufLen);//回收pcb-》子进程wait(NULL);}
}