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环境cygwin
asm/socket.h
//$ cat socket.h
/* asm/socket.h
This file is part of Cygwin.
This software is a copyrighted work licensed under the terms of the
Cygwin license. Please consult the file "CYGWIN_LICENSE" for
details. */
#ifndef _ASM_SOCKET_H
#define _ASM_SOCKET_H
#include <cygwin/if.h>
#define IOCPARM_MASK 0x7f /* parameters must be < 128 bytes */
#define IOC_VOID 0x20000000 /* no parameters */
#define IOC_OUT 0x40000000 /* copy out parameters */
#define IOC_IN 0x80000000 /* copy in parameters */
#define _IO(x,y) (IOC_VOID|(x<<8)|y)
#define _IOR(x,y,t) (IOC_OUT|(((long)sizeof(t)&IOCPARM_MASK)<<16)|(x<<8)|y)
#define _IOW(x,y,t) (IOC_IN|(((long)sizeof(t)&IOCPARM_MASK)<<16)|(x<<8)|y)
#define SIOCATMARK _IOR('s', 7, long) /* at oob mark? */
#define FIONREAD _IOR('f', 127, long) /* get # bytes to read */
#define SIOCINQ FIONREAD
/* Compatible with termios.h */
#define FIONBIO 0x8004667e /* set/clear non-blocking i/o */
#define FIOASYNC _IOW('f', 125, long) /* set/clear async i/o */
#define SIOCSHIWAT _IOW('s', 0, long) /* set high watermark */
#define SIOCGHIWAT _IOR('s', 1, long) /* get high watermark */
#define SIOCSLOWAT _IOW('s', 2, long) /* set low watermark */
#define SIOCGLOWAT _IOR('s', 3, long) /* get low watermark */
/* Needed for if queries */
#define SIOCGIFCONF _IOW('s', 100, struct ifconf) /* get if list */
#define SIOCGIFFLAGS _IOW('s', 101, struct ifreq) /* Get if flags */
#define SIOCGIFADDR _IOW('s', 102, struct ifreq) /* Get if addr */
#define SIOCGIFBRDADDR _IOW('s', 103, struct ifreq) /* Get if broadcastaddr */
#define SIOCGIFNETMASK _IOW('s', 104, struct ifreq) /* Get if netmask */
#define SIOCGIFHWADDR _IOW('s', 105, struct ifreq) /* Get hw addr */
#define SIOCGIFMETRIC _IOW('s', 106, struct ifreq) /* get metric */
#define SIOCGIFMTU _IOW('s', 107, struct ifreq) /* get MTU size */
#define SIOCGIFINDEX _IOW('s', 108, struct ifreq) /* get if index */
#define SIOGIFINDEX SIOCGIFINDEX /* backward compatibility w/ Linux typo. */
#define SIOCGIFFRNDLYNAM _IOW('s', 109, struct ifreq) /* get friendly if name */
#define SIOCGIFDSTADDR _IOW('s', 110, struct ifreq) /* Get if dstaddr */
#define SOL_SOCKET 0xffff /* options for socket level */
#define SO_DEBUG 0x0001 /* turn on debugging info recording */
#define SO_ACCEPTCONN 0x0002 /* socket has had listen() */
#define SO_REUSEADDR 0x0004 /* allow local address reuse */
#define SO_KEEPALIVE 0x0008 /* keep connections alive */
#define SO_DONTROUTE 0x0010 /* just use interface addresses */
#define SO_BROADCAST 0x0020 /* permit sending of broadcast msgs */
#define SO_USELOOPBACK 0x0040 /* bypass hardware when possible */
#define SO_LINGER 0x0080 /* linger on close if data present */
#define SO_OOBINLINE 0x0100 /* leave received OOB data in line */
#define SO_DONTLINGER (unsigned int)(~SO_LINGER)
#define SO_PEERCRED 0x0200 /* same as getpeereid */
#define SO_PASSCRED 0x0400 /* enable receiving of credentials */
/*
* Additional options.
*/
#define SO_SNDBUF 0x1001 /* send buffer size */
#define SO_RCVBUF 0x1002 /* receive buffer size */
#define SO_SNDLOWAT 0x1003 /* send low-water mark */
#define SO_RCVLOWAT 0x1004 /* receive low-water mark */
#define SO_SNDTIMEO 0x1005 /* send timeout */
#define SO_RCVTIMEO 0x1006 /* receive timeout */
#define SO_ERROR 0x1007 /* get error status and clear */
#define SO_TYPE 0x1008 /* get socket type */
#endif /* _ASM_SOCKET_H */
sys/socket.h
//$ cat sys/socket.h
/* sys/socket.h
This file is part of Cygwin.
This software is a copyrighted work licensed under the terms of the
Cygwin license. Please consult the file "CYGWIN_LICENSE" for
details. */
#ifndef _SYS_SOCKET_H
#define _SYS_SOCKET_H
#include <features.h>
#include <cygwin/socket.h>
#ifdef __cplusplus
extern "C"
{
#endif
#ifndef __INSIDE_CYGWIN_NET__
int accept (int, struct sockaddr *__peer, socklen_t *);
int accept4 (int, struct sockaddr *__peer, socklen_t *, int flags);
int bind (int, const struct sockaddr *__my_addr, socklen_t __addrlen);
int connect (int, const struct sockaddr *, socklen_t);
int getpeername (int, struct sockaddr *__peer, socklen_t *);
int getsockname (int, struct sockaddr *__addr, socklen_t *);
int listen (int, int __n);
ssize_t recv (int, void *__buff, size_t __len, int __flags);
ssize_t recvfrom (int, void *__buff, size_t __len, int __flags,
struct sockaddr *__from, socklen_t *__fromlen);
ssize_t recvmsg(int s, struct msghdr *msg, int flags);
ssize_t send (int, const void *__buff, size_t __len, int __flags);
ssize_t sendmsg(int s, const struct msghdr *msg, int flags);
ssize_t sendto (int, const void *, size_t __len, int __flags,
const struct sockaddr *__to, socklen_t __tolen);
int setsockopt (int __s, int __level, int __optname, const void *optval,
socklen_t __optlen);
int getsockopt (int __s, int __level, int __optname, void *__optval,
socklen_t *__optlen);
int shutdown (int, int);
int socket (int __family, int __type, int __protocol);
int sockatmark (int __fd);
int socketpair (int __domain, int __type, int __protocol, int __fds[2]);
struct servent *getservbyname (const char *__name, const char *__proto);
#endif
#ifdef __cplusplus
};
#endif
#if __SSP_FORTIFY_LEVEL > 0
#include <ssp/socket.h>
#endif
#endif /* _SYS_SOCKET_H */
说明
SOL_SOCKET
------------------------------------------------------------------------
SO_BROADCAST 允许发送广播数据 int
SO_DEBUG 允许调试 int
SO_DONTROUTE 不查找路由 int
SO_ERROR 获得套接字错误 int
SO_KEEPALIVE 保持连接 int
SO_LINGER 延迟关闭连接 struct linger
SO_OOBINLINE 带外数据放入正常数据流 int
SO_RCVBUF 接收缓冲区大小 int
SO_SNDBUF 发送缓冲区大小 int
SO_RCVLOWAT 接收缓冲区下限 int
SO_SNDLOWAT 发送缓冲区下限 int
SO_RCVTIMEO 接收超时 struct timeval
SO_SNDTIMEO 发送超时 struct timeval
SO_REUSERADDR 允许重用本地地址和端口 int
SO_TYPE 获得套接字类型 int
SO_BSDCOMPAT 与BSD系统兼容 int
========================================================================
IPPROTO_IP
------------------------------------------------------------------------
IP_HDRINCL 在数据包中包含IP首部 int
IP_OPTINOS IP首部选项 int
IP_TOS 服务类型
IP_TTL 生存时间 int
========================================================================
IPPRO_TCP
------------------------------------------------------------------------
TCP_MAXSEG TCP最大数据段的大小 int
TCP_NODELAY 不使用Nagle算法 int
========================================================================
链接：https://blog.csdn.net/qq_41097897/article/details/82845404
