Linux:C语言编程:fread
fread
函数名: fread
功 能: 从一个流中读数据
用 法: int fread(void *ptr, int size, int nitems, FILE *stream);
参 数:用于接收数据的地址(ptr)
单个元素的大小(size)
元素个数(nitems)
提供数据的文件指针(stream)
返回值:成功读取的元素个数
程序例:
#include <string.h>
#include <stdio.h>
int main(void)
{
FILE *stream;
char msg[] = "this is a test";
char buf[20];
if ((stream = fopen("DUMMY.FIL", "w+"))
== NULL)
{
fprintf(stderr,
"Cannot open output file.\n");
return 1;
}
/* write some data to the file */
fwrite(msg, strlen(msg)+1, 1, stream);
/* seek to the beginning of the file */
fseek(stream, SEEK_SET, 0);
/* read the data and display it */
fread(buf, 1, strlen(msg)+1, stream);
printf("%s\n", buf);
fclose(stream);
return 0;
}