C语言：读写文件file

file_read.c

#include <stdio.h>

#define STR_BUFF_MAX 10

int main() {
    FILE *fp;
    char str[STR_BUFF_MAX] = {0}; // 初始化为全0
 
    fp = fopen("test.txt", "r"); // 打开文件
    if(fp == NULL) {
        printf("open failed.\n");
        return 1;
    }
    fread(str, sizeof(char), sizeof(str), fp); // 读取数据
    fclose(fp); // 关闭文件
    
    str[STR_BUFF_MAX - 1] = '\0'; // 串结束符防止溢出
    printf("%s", str);
    return 0;
}

file_write.c

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

#define STR_BUFF_MAX 10

void PrintHelp(void)
{
    printf("****************************************************\n");
    printf("* Usage:                                            \n");
    printf("*        filewrite <file name> <file context>       \n");
    printf("*        filewrite test.txt 12345678ABCDEFG         \n");
    printf("*                                                   \n");
    printf("****************************************************\n");
}

int main(int argc, char *argv[]) {
    FILE *fp = NULL;
    int i;

    if (argc != 3) {
        PrintHelp();
        return -1;
    }
    fp = fopen(argv[1], "w"); // 打开文件
    if(fp == NULL) {
        printf("open file: %s failed.\n", argv[1]);
        return 1;
    }
    fwrite(argv[2], sizeof(char), strlen(argv[2]) + 1, fp); // 写入数据
 
    fclose(fp); // 关闭文件
    return 0;
}

makefile

all : fileread filewrite

fileread : file_read.c
	gcc file_read.c -o fileread

filewrite : file_write.c
	gcc file_write.c -o filewrite