Question

linux下使用fread和fwrite的问题：我想实现一个文件到另一个文件的简单复制，总是编译出错.

#include <stdio.h>
#include <stdlib.h>
#define BUFSIZE 1024
void cp(FILE *source,FILE *dest);
int main(int argc,char *argv[])
{
FILE *fp1,*fp2;
if(argc!=3)
{
fprintf(stderr,"Usage:%s filename1 filename2\n",argv[0]);
exit(EXIT_FAILURE);
}
if((fp1=fopen(argv[1],"rb"))==NULL)
{
fprintf(stderr,"Cann't open file %s.\n",argv[1]);
exit(EXIT_FAILURE);
}
if(setvbuf(fp1,NULL,_IOFBF,BUFSIZE)!=0)
{
fprintf(stderr,"Error in creat buffers.\n");
exit(EXIT_FAILURE);
}
if((fp2=fopen(argv[2],"wb"))==NULL)
{
fprintf(stderr,"Cann't open file %s.\n",argv[2]);
exit(EXIT_FAILURE);
}
if(setvbuf(fp2,NULL,_IOFBF,BUFSIZE)!=0)
{
fprintf(stderr,"Error in creat buffers.\n");
exit(EXIT_FAILURE);
{
cp(fp1,fp2);
if(ferror(fp1)!=0)
{
fprintf(stderr,"Error in reading %s.\n",argv[1]);
//exit(EXIT_FAILURE);
}
if(ferror(fp2)!=0)
{

fprintf(stderr,"Error in writing %s.\n",argv[2]);
// exit(EXIT_FAILURE);
}
if(fclose(fp1)!=0)
{

fprintf(stderr,"Error in closing %s.\n",argv[1]);
exit(EXIT_FAILURE);
}
if(fclose(fp2)!=0)
{

fprintf(stderr,"Error in closing %s.\n",argv[2]);
exit(EXIT_FAILURE);
}
return 0;
}

void cp(FILE *source,FILE *dest)
{

size_t bytes;
static char temp[BUFSIZE];
while((bytes=fread(temp,sizeof(char),BUFSIZE,source))>0)
fwrite(temp,sizeof(char),bytes,dest);
}
gcc 编译总是出错：parse error at end of input。

Answer 1

最好用fgets()来读取一行，该函数自动读取一行。
写的时候你就可以自己随意定啦！你在buf后面加个换行符'\n'就行了，fwrite()就会自动换行了。
比如：
FILE* fp = fopen("c:\\test.txt","rw"); //打开文件
if( fp == NULL )
return;
char achBuf[256] = ;
fgets( achBuf,fp ); //读取一行，直到遇到换行符结束
memset( achBuf,0,256 );
strcpy(achBuf,"Hello,world!\n"); //内容随意，别忘了加个换行符
fwrite( achBuf,1,strlen(achBuf)+1,fp ); //写入一行
fclose(fp); //关闭文件

Answer 2

if(setvbuf(fp2,NULL,_IOFBF,BUFSIZE)!=0)
{
fprintf(stderr,"Error in creat buffers.\n");
exit(EXIT_FAILURE);
{
cp(fp1,fp2);
看到没有，这么明显的错误，一个括号方向打反了，改成 }运行ok。

Answer 3

﹌