一、打开文件

[c]
#include <stdio.h>
#include <stdlib.h>

main(){

	FILE *fp;

	fp = fopen("test", "r");

	if(fp == NULL){
	// 打开操作不成功
	    printf("The file can not be opened.\n");
	    exit(1);
	}

}
[/c]

二、读取文件

[c]

#include <stdio.h>
#include <stdlib.h>

main(){

	int str;
	FILE *fp;

	fp = fopen("test", "r");

	str = fgetc(fp); // 读取一个字符

	if(str != EOF){
		putchar(str);
	}

	fclose(fp);

}

[/c]

三、读取一行

[c]

#include <stdio.h>
#include <stdlib.h>

main(){

	char str[1024];
	FILE *fp;

	fp = fopen("test", "r");

	fgets(str, 1024, fp);

	printf("%s\n", str);

	fclose(fp);

}

[/c]

四、写入文件

[c]
#include <stdio.h>

main(){

	FILE *fp;

	fp = fopen("test", "w");

	fputs("this is test\n", fp);

	fclose(fp);

}
[/c]

五、其他