《UNIX环境高级编程》笔记--读和写流

一旦打开了流，则可以对流进行读写：每次一个字符，每次一行，二进制。

1.每次一个字符使用下面三个函数用于一次读一个字符。

#include <stdio.h>typedef struct{        int a;        char b;}myst;int main(void){        int result = 0;        FILE* fp;        myst st1,st2;        st1.a = 1;        st1.b = 'a';        if((fp = fopen("bfile","wb+")) == NULL){                result = -1;                perror("fopen");                goto FINALLY;        }        if(fwrite(&st1, sizeof(myst), 1, fp) < 0){                result = -1;                perror("fwrite");                goto FINALLY;        }        fclose(fp);        if((fp = fopen("bfile","rb+")) == NULL){                result = -1;                perror("fopen");                goto FINALLY;        }        if(fread(&st2, sizeof(myst), 1, fp) < 0){                result = -1;                perror("fread");                goto FINALLY;        }        printf("st2.a=%d\n",st2.a);        printf("st2.b=%c\n",st2.b);FINALLY:        if(fp != NULL){                fclose(fp);        }        return result;}

运行结果：yan@yan-vm:~/apue$ ./a.out
st2.a=1
st2.b=a