APUE-1.2 将标准输入复制到标准输出(read(),write())

/* 1-2 将标准输入复制到标准输出(read(),write()) *//*  read(),write(),perror()*/#include <unistd.h>#include <stdio.h>/* perror() */#include <errno.h>/* perror() */#include <stdlib.h>/* exit() */#define BUFFSIZE 4096int main(){int n;char buf[BUFFSIZE];while( (n = read(STDIN_FILENO, buf, BUFFSIZE)) > 0 ){if( (write(STDOUT_FILENO, buf, n)) != n ){perror("write error");exit(1);}}if(n < 0){perror("read error");exit(1);}return 0;}