socket设定连接超时如何设置？

[icewolf_li]

java里面是setSoTimeout()就可以设定socket连接的连接响应超时，
请问C里面如何做？好像如果用select方法有个timeout参数，但如果我不用select怎么办？
本人C不熟，各位指点一下了。
最好告知windows和unix下的方法，或者函数名。

[晨星]

只知道windows socket2库中可以使用setsockopt设置同步socket的发送和接收消息的超时时间。

如：
socket sock;
……
……
int iSendTime = 5000;//5秒
int iRecvTime = 5000;
setsockopt(sock, SOL_SOCKET, SO_SNDTIMEO, (const char*)&iSendTime, sizeof(iSendTime));
setsockopt(sock, SOL_SOCKET, SO_RCVTIMEO, (const char*)&iRecvTime, sizeof(iRecvTime));

[晨星]

关于sotsockopt的用法，可以查MSDN。

[MagicCarmack]

MSDN

[cc1q]

帮顶一下~~~

[cnman]

UNIX下一般是通过SIGNAL设置的超时信号实现。

[liuleilover]

一般在socket创建后就可以用setsockopt设置Recv/Send超时，而且在任何时候修改。
如果想设置Connect/Accept超时只能用Select实现

[suyun9329]

up

[icewolf_li]

connect的超时呢？unix下呢？

[ghostsG]

up

[yeehya]

这个超时的时间是不是由相关协议来确定的吧~
难道要修改协议中的某些值~?

[yeehya]

帮顶一下~~~
期待答案

[wtogether]

//xnet_select x defines
#define READ_STATUS 0
#define WRITE_STATUS 1
#define EXCPT_STATUS 2

/*
s - SOCKET
sec - timeout seconds
usec - timeout microseconds
x - select status
*/
int xnet_select(SOCKET s, DWORD sec, DWORD usec, BYTE x)
{
int st = SOCKET_ERROR;
struct timeval to;
fd_set fs;
to.tv_sec = sec;
to.tv_usec = usec;
FD_ZERO(&fs);
FD_SET(s, &fs);
switch(x)
{
case READ_STATUS:
st = select(s+1, &fs, 0, 0, &to);
break;
case WRITE_STATUS:
st = select(s+1, 0, &fs, 0, &to);
break;
case EXCPT_STATUS:
st = select(s+1, 0, 0, &fs, &to);
break;
}
return(st);
}

[icewolf_li]

wtogether(wtogether) :
这是unix下的实现方式？

下面是简单的socket连接。要怎么改？

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stdarg.h>
#include <errno.h>
#ifdef WIN32
#include <winsock2.h>
#else
#include <unistd.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <netdb.h>
#endif

#ifndef INADDR_NONE
#define INADDR_NONE 0xffffffff
#endif
#define MAX_STRING_LEN 2048
#define BUFSIZE 1024

char hostname[MAX_STRING_LEN];
char buf[BUFSIZE];

static char i_host[MAX_STRING_LEN]; /* site name the web cache sitting in */
static char i_port[MAX_STRING_LEN]; /* port number invalidator listens on */
static char i_pass[MAX_STRING_LEN]; /* password of user invalidator */
static char i_uriprefix[MAX_STRING_LEN]; /* Specify the prefix path of the documents to be invalidated. The prefix path must begin with http|https://host_name:port/path/filename or "/" and end with "/". */
static char i_uri[MAX_STRING_LEN]; /* Specify the URL of the documents to be invalidated underneath the URIPREFIX */
static int i_verbose = 1;

char http_POST[] = "POST /x-oracle-cache-invalidate HTTP/1.0\r\n";
char http_ContentLength[BUFSIZE];
char http_Authorization[MAX_STRING_LEN];

void err_doit(int errnoflag, const char *fmt, va_list ap);
void err_quit(const char *fmt, ...);
int tcp_connect(const char *host, const unsigned short port);
void print_usage();

int tcp_connect(const char *host, const unsigned short port)
{
char * transport = "tcp";
struct hostent *phe; /* pointer to host information entry */
struct protoent *ppe; /* pointer to protocol information entry*/
struct sockaddr_in sin; /* an Internet endpoint address */
int s; /* socket descriptor and socket type */

#ifdef WIN32
{
WORD wVersionRequested;
WSADATA wsaData;
int err;

wVersionRequested = MAKEWORD( 2, 0 );

err = WSAStartup( wVersionRequested, &wsaData );
if ( err != 0 ) {
/* Tell the user that we couldn't find a usable */
/* WinSock DLL. */
printf("can't initialize socket library\n");
exit(0);
}
}
#endif

memset(&sin, 0, sizeof(sin));
sin.sin_family = AF_INET;

if ((sin.sin_port = htons(port)) == 0)
err_quit("invalid port \"%d\"\n", port);

/* Map host name to IP address, allowing for dotted decimal */
if ( phe = gethostbyname(host) )
memcpy(&sin.sin_addr, phe->h_addr, phe->h_length);
else if ( (sin.sin_addr.s_addr = inet_addr(host)) == INADDR_NONE )
err_quit("can't get \"%s\" host entry\n", host);

/* Map transport protocol name to protocol number */
if ( (ppe = getprotobyname(transport)) == 0)
err_quit("can't get \"%s\" protocol entry\n", transport);

/* Allocate a socket */
s = socket(PF_INET, SOCK_STREAM, ppe->p_proto);
if (s < 0)
err_quit("can't create socket: %s\n", strerror(errno));

/* Connect the socket */
if (connect(s, (struct sockaddr *)&sin, sizeof(sin)) < 0)
err_quit("can't connect to %s:%d\n", host, port);
return s;
}

void err_doit(int errnoflag, const char *fmt, va_list ap)
{
int errno_save;
char buf[MAX_STRING_LEN];

errno_save = errno;
vsprintf(buf, fmt, ap);
if (errnoflag)
sprintf(buf + strlen(buf), ": %s", strerror(errno_save));
strcat(buf, "\n");
fflush(stdout);
fputs(buf, stderr);
fflush(NULL);
return;
}

/* Print a message and terminate. */
void err_quit(const char *fmt, ...)
{
va_list ap;
va_start(ap, fmt);
err_doit(0, fmt, ap);
va_end(ap);
exit(1);
}

#ifdef WIN32
char *optarg;

char getopt(int c, char *v[], char *opts)
{
static int now = 1;
char *p;

if (now >= c) return EOF;

if (v[now][0] == '-' && (p = strchr(opts, v[now][1]))) {
optarg = v[now+1];
now +=2;
return *p;
}

return EOF;
}

#else
extern char *optarg;
#endif

#define required(a) if (!a) { return -1; }

int init(int argc, char *argv[])
{
char c;
int i,optlen;
int slashcnt;

i_host[0] = '\0';
i_port[0] = '\0';

//printf("%d\n%s\n",argc,argv[7]);
while ((c = getopt(argc, argv, "h:p:?")) != EOF) {
//printf("%c\n",c);
if (c == '?')
return -1;
switch (c) {
case 'h':
required(optarg);
strcpy(i_host, optarg);
break;
case 'p':
required(optarg);
strcpy(i_port, optarg);
break;
default:
return -1;
}
}

/*
* there is no default value for hostname, port number,
* password or uri
*/
if (i_host[0] == '\0' || i_port[0] == '\0')
return -1;

return 1;
}

void print_usage()
{
char *usage[] =
{
"Usage:",
" -h host name",
" -p port",
"example:",
" -h 127.0.0.1 -p 4001",
};
int i;

for (i = 0; i < sizeof(usage) / sizeof(char*); i++)
printf("%s\n", usage[i]);

return;
}

#ifdef WIN32
#define write(a, b, c) send(a, b, c, 0)
#define read(a, b, c) recv(a, b, c, 0)
#endif

int main(int argc, char *argv[])
{
int fd;
int n;

/* parse command line etc ... */
if (init(argc, argv) < 0) {
print_usage();
exit(1);
}

buf[0] = '\0';

/* pack the info into the buffer */
strcpy(buf, "HelloWorld");

/* make connection to the server */
fd = tcp_connect(i_host, (unsigned short)atoi(i_port));

/* send off the message */
write(fd, buf, strlen(buf));

/* display the server response */
printf("Server response:\n");
n = read(fd, buf, BUFSIZE);
buf[n] = '\0';
printf("%s\n", buf);


#ifdef WIN32
WSACleanup();
#endif

return 0;
}

[yeehya]

cnman(不明) ---UNIX下一般是通过SIGNAL设置的超时信号实现。
__________________________________________________________
严重同意!
可以这样:
global_v: int connflag = 0;
in main:
{
signal(SIGALRM, alarm_handler);//对由alarm产生的SIGALRM信号设定自己定义的处理函数.
alarm(Time_YouWant);
if(connect ()>=0)
connflag = 1;
else
//error handle!
}
in alarm_handler:
{
if(connflag) //ok!
//just return to main!
else //timeout
//do someting before exit()!
}
不知道这样可不可以,也是初学,:-)

[ghostsG]

up.我也想知道

[wtogether]

那个扩展的xnet_select函数是通用的，在不同的OS下用不同的头文件而已，win32和unix下都可以用
用的时候这么用：
if (xnet_select(fd, 0, 500, WRITE_STATUS)>0) write(fd, buf, strlen(buf));

/* display the server response */
printf("Server response:\n");
while (xnet_select(fd, 3, 0, READ_STATUS)>0)
{
if ((n=read(fd, buf, BUFSIZE))==-1) break;
buf[n] = '\0';
printf("%s\n", buf);
}

[zhousqy]

up

[tcprince]

为什么要不用select()呢？难道就因为不熟吗？不用怎么熟？

[icewolf_li]

ok.大致明白了。先揭帖。