c - 逐行添加

Question

我目前必须添加并使其按这样的顺序进行

content of file 1
content of file 2
content of file 1
content of file 2

它目前只将一个文本文件的内容写入输出文件，我看不出我哪里出错了，所以非常感谢任何帮助。

**** 编辑，嗨做了一些挖掘，发现这个确切的问题已经得到回答，不想惹上 mods 的麻烦，也无法删除，谢谢大家

Answer 1

您没有存储 fopen() 返回的流指针，也没有交错 file1 和 file2 的行。以下是解决这些问题的方法:

    ...
    // file 3
    printf("Please enter the name of the output file : ");
    if (scanf("%s", file3) != 1) {
        printf("input error\n");
        exit(1);
    }    
    FILE *OpenFile = fopen(file1, "r");
    FILE *OpenFile2 = fopen(file2, "r");
    FILE *OpenFile3 = fopen(file3, "w");

    if (OpenFile == NULL || OpenFile2 == NULL || OpenFile3 == NULL) {
        perror("Error opening files");
        printf("Press any key to exit!\n");
        exit(1);
    }

    int c1 = 0, c2 = 0;
    while (c1 != EOF || c2 != EOF) {
        if (c1 != EOF) {
            /* copy a line from file1 */
            while ((c1 = fgetc(OpenFile)) != EOF && c1 != '\n') {
                fputc(c1, OpenFile3);
            }
            fputc('\n', OpenFile3);
        }
        if (c2 != EOF) {
            /* copy a line from file2 */
            while ((c2 = fgetc(OpenFile)) != EOF && c2 != '\n') {
                fputc(c2, OpenFile3);
            }
            fputc('\n', OpenFile3);
        }
    }

    printf("The two files were successfully merged into %s\n", file3);

    fclose(OpenFile);
    fclose(OpenFile2);
    fclose(OpenFile3);
    return 0;