使用新文件扩展名

Question

我试图让用户输入他们想要我读取的输入文件，我想将一个输入保存到两个变量中，输入文件将是＆＃34; file.txt＆＃34 ;，但我希望输出文件是＆＃34; file.txt.cvt＆＃34;

目前我遇到了问题。

这就是我所拥有的

printf("Enter file name: "); //asks for filename from user
    scanf("%s %s.cvt", input_file, output_file);      //stores string as "filename"

    inputf = fopen(input_file, "r"); /*file open stored string as
                                     read only. 'filename, "r"'*/

    outputf = fopen(output_file, "w");

Answer 1

strcpy(output_file, input_file); // Make a copy of the input file name
strcat(output_file, ".cvt"); // Add the ".cvt" suffix to it