动态加载共享库，这个知识点书上简单提了下，我做了个简单例子加深印象
main.c
#include <stdio.h>
#include <dlfcn.h> int main(int argc, char** argv)
{
void* handle = dlopen ("libreciprocal .so", RTLD_LAZY);
double (*reciprocal)(int) = dlsym (handle, "reciprocal");
int num;
num = atoi(argv[1]);
printf(“%d 的倒数是%g/n”,num, reciprocal(num));
dlclose (handle);
return 0;
}
#include <dlfcn.h> int main(int argc, char** argv)
{
void* handle = dlopen ("libreciprocal .so", RTLD_LAZY);
double (*reciprocal)(int) = dlsym (handle, "reciprocal");
int num;
num = atoi(argv[1]);
printf(“%d 的倒数是%g/n”,num, reciprocal(num));
dlclose (handle);
return 0;
}
reciprocal.hpp
#ifdef __cplusplus
extern "C" {
#endif
extern double reciprocal (int i);
#ifdef __cplusplus
}
#endif
extern "C" {
#endif
extern double reciprocal (int i);
#ifdef __cplusplus
}
#endif
reciprocal.cpp
#include <cassert>
#include "reciprocal.hpp"
double reciprocal (int i) {
// I should be non-zero.
assert (i != 0);
return 1.0/i;
}
#include "reciprocal.hpp"
double reciprocal (int i) {
// I should be non-zero.
assert (i != 0);
return 1.0/i;
}
具体编译过程:
注：这里我将共享库放置在/home/phinecos/lib下，