系统调用IO/C库函数IO

open      int fd1 = open("fifo1", O_WRONLY);  O_RDONLY  O_WRONLY

read       read(STDIN_FILENO,buf,sizeof(buf));   STDOUT_FILENO  STDIN_FILENO

write

close

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fopen      

fgets

fputs

fread  第一个参数是buf  第二个参数是读取的最小结构的字节大小 第三个参数是结构的数量 如果读取到的结构数量小于第二个参数的字节大小,那么fread返回0

fwrite

fclose

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FOPEN/FCLOSE 使用

int main(int arg, char *args[]) {

FILE *p1 = fopen("a.txt", "r");

if (p1 == NULL) {

printf("err is %s\n", strerror(errno));

return -1;

}

int buf[1024];

memset(buf, 0, sizeof(buf));

char val[32];

int len = 0;

while (1) {

memset(val, 0, sizeof(val));

if (fgets(val, sizeof(val), p1) == NULL) {

break;

}

buf[len] = atoi(val);

len++;

}

fclose(p1);

FILE *p2 = fopen("b.txt", "w");

if (p2 == NULL) {

printf("err is %s\n", strerror(errno));

return -1;

}

int i;

for (i = 0; i < len; i++) {

memset(val,0,sizeof(val));

sprintf(val,"%d\n",buf[i]);

fputs(val,p2);

}

fclose(p2);

return 0;

}

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