#include "unp.h" void str_echo(int sockfd) { long arg1, arg2; ssize_t n; char line[MAXLINE]; for ( ; ; ) { if ( (n = Readline(sockfd, line, MAXLINE)) == 0) return; /* connection closed by other end */ if (sscanf(line, "%ld%ld", &arg1, &arg2) == 2) snprintf(line, sizeof(line), "%ld\n", arg1 + arg2); else snprintf(line, sizeof(line), "input error\n"); n = strlen(line); Writen(sockfd, line, n); } }