cc -O3 -DIPv6 -DKILLLIST -DUSE_SSL -c -Wall biffpop.c -o biffpop.o biffpop.c:24:25: error: openssl/ssl.h: No such file or directory biffpop.c:25:25: error: openssl/err.h: No such file or directory biffpop.c:47: error: expected ‘=’, ‘,’, ‘;’, ‘asm’ or ‘__attribute__’ before ‘*’ token biffpop.c: In function ‘main’: biffpop.c:124: error: ‘_RE_SYNTAX_POSIX_COMMON’ undeclared (first use in this function) biffpop.c:124: error: (Each undeclared identifier is reported only once biffpop.c:124: error: for each function it appears in.) biffpop.c:127: warning: implicit declaration of function ‘SSL_load_error_strings’ biffpop.c:128: warning: implicit declaration of function ‘SSL_library_init’ biffpop.c:129: error: ‘ctx’ undeclared (first use in this function) biffpop.c:129: warning: implicit declaration of function ‘SSL_CTX_new’ biffpop.c:129: warning: implicit declaration of function ‘SSLv23_client_method’ biffpop.c:130: warning: implicit declaration of function ‘ERR_print_errors_fp’ biffpop.c:138: warning: implicit declaration of function ‘SSL_CTX_free’ biffpop.c:139: warning: implicit declaration of function ‘ERR_free_strings’ biffpop.c: In function ‘readConfigFileSub’: biffpop.c:439: warning: implicit declaration of function ‘re_compile_pattern’ biffpop.c:440: warning: assignment makes pointer from integer without a cast make: *** [biffpop.o] Error 1