C语言之读/写(fread/fwrite)文件(五十八)

#include <stdio.h>
#include <string.h>
#include <stdbool.h>

int main(){
	FILE *fp;
	char c[] = "1234567789233456764436433464384364384364384364384374384743843";
	char buffer[20]={0};
  int len = 0;

	//1.write text to file.txt
	fp = fopen("file.txt", "w");
	fwrite(c, 1, strlen(c), fp);
	fclose(fp);

	//2.read text from file.txt
	fp = fopen("file.txt", "r");
	while(1){
		len = fread(buffer, 1, 20, fp);
		printf("xxx---------------->line = %d, len = %d\n",__LINE__,len);
		if(len > 0 && len < 20){
			printf("xxx---------------->line = %d, len = %d\n",__LINE__,len);
			fread(buffer, 1, len, fp);
		}else if(len == 0){
			printf("xxx---------------->line = %d\n",__LINE__);
			break;
		}
	}

	fclose(fp);

	return(0);
}