C++设置和获取环境变量

#include <stdlib.h>
int main(int argc, char **argv)
{
const char* python_home = getenv("PYTHONHOME");
char new_python_home[256];
new_python_home[0] = 0;
if(python_home)
{
#ifdef _DEBUG
#ifdef _WIN64
sprintf(new_python_home, "PYTHONHOME=%s\\win64\\debug", python_home);
//printf("win64 debug\n");
#elif defined(_WIN32)
sprintf(new_python_home, "PYTHONHOME=%s\\win32\\debug", python_home);
//printf("win32 debug\n");
#endif
#else
#ifdef _WIN64
sprintf(new_python_home, "PYTHONHOME=%s\\win64\\release", python_home);
//printf("win32 release\n");
#elif defined(_WIN32)
sprintf(new_python_home, "PYTHONHOME=%s\\win32\\release", python_home);
//printf("win32 release\n");
#endif
#endif
if(new_python_home[0])
_putenv(new_python_home);
}
printf("%s\n", getenv("PYTHONHOME"));
}