fat.cpp: In function 'int main()': fat.cpp:9: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result fat.cpp:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result fat.cpp:11: warning: ignoring return value of 'char* gets(char*)', declared with attribute warn_unused_result fat.cpp:13: warning: ignoring return value of 'char* gets(char*)', declared with attribute warn_unused_result fat.cpp:15: warning: ignoring return value of 'char* gets(char*)', declared with attribute warn_unused_result /tmp/ccBJD5xz.o: In function `main': fat.cpp:(.text+0x60): warning: the `gets' function is dangerous and should not be used.