还有就是为什么:dlopen()报的错 ,但是明确的是可以找到SO文件？

Question

#include "stdio.h"#include "stdlib.h"#include "dlfcn.h"int main(void){int (*So)(const char* pszTimestamp, const char* pszSDRType, const char* pszCallID,const char* pszUserNo, const char* pszCallerNo, const char* pszCalledNo,const char* pszOldNumber, const char* pszLocationID, const char* pszField1,const char* pszField2, const char* pszField3, const char* pszField4);const char *errmsg = "";printf("begin!\n");void *SoLib = dlopen("/root/RecordDll//Release/libRecordDll.so", RTLD_LAZY);printf("111");if (NULL == SoLib){printf("222");fprintf(stderr, "Failed to load libRecordDll.so:%s\n", dlerror());return 1;}dlerror();printf("333");*(void **)(&So) = dlsym(SoLib, "GetInfo");printf("444");if (NULL != (errmsg = dlerror())){printf("%s\n", errmsg);return 1;}printf("555");int ret = So("2011-11-11 11:11:11", "8", "11","111", "1111", "11111","111111", "1111111", "1~1~1","2011-11-11 11:11:11~2012-11-11 11:11:11~0~03", "", "");printf("%d", ret);dlclose(SoLib);return 0;}

Answer 1

你这段代码应该没问题，我那libstdc++试过了，没错。
问题应该在你的/root/RecordDll//Release/libRecordDll.so，
这个动态库GetInfo函数有bug。指针错误或者数据越界。
我这代码：
#include <stdio.h>
#include <stdlib.h>
#include <dlfcn.h>

int main(void)
{
// /usr/lib/libstdc++.so.6
int (*mygetchar)(void);
const char *errmsg = "";

printf("begin!\n");
void *SoLib = dlopen("/usr/lib/libstdc++.so.6", RTLD_LAZY);

printf("111\n");

if (NULL == SoLib)
{
printf("222\n");
fprintf(stderr, "Failed to load libstdc++.so.6:%s\n", dlerror());
return 1;
}

dlerror();

printf("333\n");

*(void **)(&mygetchar) = dlsym(SoLib, "getchar");//

printf("444\n");

if (NULL != (errmsg = dlerror()))
{
printf("%s\n", errmsg);
return 1;
}

printf("555\n");

int ret = mygetchar();

printf("%d\n", ret);

dlclose(SoLib);
return 0;

}

上面代码跑没问题的，你的要错就是在动态库本身了。

“还有就是:dlopen()报的错 ,但是明确的是可以找到SO文件,”

/root/RecordDll//Release/libRecordDll.so

看到了，/RecordDll//Release这中间多了一根右斜杆，路径错误，找到就见鬼了。

Answer 2

应该是有个指针指错了