c - 文件处理 : Extra characters in output

Question

#include <stdio.h>

int main () {

    FILE *fp;
    char ch;
    char data[100];
    int i;

    fp = fopen("file.txt","r");

    i=0;

    while( (ch=fgetc(fp)) != EOF) {
            data[i]=ch;
            i++;
    }

    i=0;

    while(data[i]) {
            printf("%c",data[i]); 
            i++;
    }

 return 0;

 }

文件.txt的内容:

udit@udit-Dabba /opt/lampp/htdocs $ cat file.txt 
aGVsbG9teW5hbWVpc2toYW4K

程序输出:

udit@udit-Dabba /opt/lampp/htdocs $ sudo vim test.c
udit@udit-Dabba /opt/lampp/htdocs $ sudo gcc test.c
udit@udit-Dabba /opt/lampp/htdocs $ ./a.out
aGVsbG9teW5hbWVpc2toYW4K
P�udit@udit-Dabba /opt/lampp/htdocs $ 

为什么这两个额外的字符出现在数组的输出中...？？？输入文件实际上是base-64编码的结果。

Answer 1

fgetc返回 int 而不是 char。

看看这是否适合你:

#include <stdio.h>

int main (void) {

    FILE *fp;
    int ch;
    int data[100] = { 0 }; // Easiest way of initializing the entire array to 0
    int i;

    fp = fopen("file.txt","r");

    i=0;

    while( (ch=fgetc(fp)) != EOF) {
            data[i]=ch;
            i++;
    }

//        data[i]=0; -->You did not provide a terminating point - 
// Not needed if the array is initialized the way i did.

    i=0;

    while(data[i]) {
           printf("%c",data[i]); 
            i++;  }
 return 0;

 }