Compilare: user.cpp: In function ‘int main()’: user.cpp:42: warning: unused variable ‘offset’ user.cpp:56: warning: unused variable ‘o’ user.cpp:50: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result user.cpp:51: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result user.cpp:54: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result