小编DaR*_*f0x的帖子

我已经设法打开一个文件并在用var=fopen(file,"r")/ 写入另一个文件时读取,"w"但即使用r +或w +模式我也无法打开文件并改变其内容.

想象一下:

int formatacao (char original[]){/*se a cadeia nao tiver escrita em maiusculas, esta funçao vai alteralas para tal*/
    int val1;
    FILE * original_open;

    original_open = fopen (original,"r+");

    if (original_open==0){
       printf ("ficheiro %c 1.",original);
    }


    while ((val1=fgetc(original_open))!=EOF){
          if (val1>='a'&&val1<='z'&&val1){
             fputc(val1-32,original_open);
          }
          else 
          fputc(val1,original_open);
    }

    fclose (original_open);
    return (0);
}

代码工作,没有错误,没有警告,唯一的问题是:如果我像这样使用它,它会删除文件中的内容但是这样可行:

int main (){
    int val1,val2,nr=0;
    FILE* fp1;
    FILE* fp2;
    fp1=fopen ("DNAexample.txt","r");
    fp2=fopen ("DNAexample1.txt","w");
    if (fp1==0){
       printf ("EPIC FAIL no 1.\n");
    }
    while ((val1=fgetc(fp1))!=EOF){ …