c++ - 包括 错误 : field has incomplete type 'struct xsocket'

Question

我正在处理的项目有以下内容

#include <memory.h>
#include <signal.h>
#include <errno.h>
#include <arpa/inet.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/sysctl.h>
#include <sys/socket.h>
#ifdef __linux__
#  include <linux/tcp.h>
#else
#  include <sys/time.h>
#  include <netinet/in.h>
#  include <netinet/tcp.h>
#  include <netinet/tcp_var.h>
#endif

我正在 64 位 Mac 上编译。当到达 tcp_var.h 包含时，编译器会抛出以下错误:

/usr/include/netinet/in_pcb.h:192:17: error: field has incomplete type 'struct xsocket'
        struct  xsocket xi_socket;
                        ^
/usr/include/netinet/in_pcb.h:192:9: note: forward declaration of 'xsocket'
        struct  xsocket xi_socket;
                ^
/usr/include/netinet/in_pcb.h:235:20: error: field has incomplete type 'struct xsocket64'
        struct  xsocket64 xi_socket;
                          ^
/usr/include/netinet/in_pcb.h:235:10: note: forward declaration of 'xsocket64'
        struct  xsocket64 xi_socket;
                ^
/usr/include/netinet/in_pcb.h:245:2: error: unknown type name 'so_gen_t'
        so_gen_t        xig_sogen;      /* current socket generation count */
        ^
In file included from .../tcp_client_listener.cc:52:
/usr/include/netinet/tcp_var.h:373:25: error: field has incomplete type 'struct xsocket'
        struct  xsocket xt_socket;
                        ^
/usr/include/netinet/in_pcb.h:192:9: note: forward declaration of 'xsocket'
        struct  xsocket xi_socket;
                ^
/Users/Justin/Projects/smartdevicelink/SDL_Core/src/components/transport_manager/src/tcp/tcp_client_listener.cc:141:44: error: use of undeclared identifier
      'TCP_USER_TIMEOUT'
    setsockopt(connection_fd, IPPROTO_TCP, TCP_USER_TIMEOUT, &user_timeout, sizeof(user_timeout));

是否有不同的库可以包含在 #ifdef MAC_OSX 指令之间或修复此前向声明并保持与其他 mac 的兼容性的方法？

Answer 1

这完全取决于您导入 header 的顺序!

这个命令有效

#import <sys/socketvar.h>
#import <netinet/in.h>
#import <netinet/tcp_var.h>
#import <netinet/tcp.h>
#import <sys/socket.h>