$ gcc -o test.exe test.c -lwpcap test.c:1: error: parse error before '<' token test.c:6: error: `PCAP_ERRBUF_SIZE' undeclared here (not in a function) test.c:13: error: parse error before "if" test.c:22: warning: parameter names (without types) in function declaration test.c:22: warning: data definition has no type or storage class test.c:23: error: parse error before "return" test.c:6: error: storage size of `errbuf' isn't known test.c:8: error: storage size of `fcode' isn't known