codeexm4.txt

《计算机网络与因特网》(原书第4版) 作者:Douglas Comer博士 出版社：机械工业出版社 书中例子的代码

/* echoserver.c */

#include <stdlib.h>
#include <stdio.h>
#include <cnaiapi.h>

#define BUFFSIZE		256

/*-----------------------------------------------------------------------
 *
 * Program: echoserver
 * Purpose: wait for a connection from an echoclient and echo data
 * Usage:   echoserver <appnum>
 *
 *-----------------------------------------------------------------------
 */
int
main(int argc, char *argv[])
{
	connection	conn;
	int		len;
	char		buff[BUFFSIZE];

	if (argc != 2) {
		(void) fprintf(stderr, "usage: %s <appnum>\n", argv[0]);
		exit(1);
	}

	/* wait for a connection from an echo client */

	conn = await_contact((appnum) atoi(argv[1]));
	if (conn < 0)
		exit(1);

	/* iterate, echoing all data received until end of file */

	while((len = recv(conn, buff, BUFFSIZE, 0)) > 0)
		(void) send(conn, buff, len, 0);
	send_eof(conn);
	return 0;
}