int main() {
    printf("=== File I/O Tests ===\n");

    printf("Test 1: Writing to a file\n");
    int f = fopen("test_output.txt", "w");
    if (f == 0) {
        printf("ERROR: Could not open file for writing\n");
        return 1;
    }
    fputs(f, "Hello, File I/O!\n");
    fputs(f, "This is line 2.\n");
    fputs(f, "Testing file operations.\n");
    fclose(f);
    printf("PASS: File written successfully\n");

    printf("Test 2: Reading from file using fgets\n");
    f = fopen("test_output.txt", "r");
    if (f == 0) {
        printf("ERROR: Could not open file for reading\n");
        return 1;
    }
    char *line1 = fgets(f, 256);
    printf("Line 1: %s", line1);
    char *line2 = fgets(f, 256);
    printf("Line 2: %s", line2);
    char *line3 = fgets(f, 256);
    printf("Line 3: %s", line3);
    fclose(f);
    printf("PASS: File read successfully\n");

    printf("Test 3: File position operations\n");
    f = fopen("test_output.txt", "r");
    if (f == 0) {
        printf("ERROR: Could not open file\n");
        return 1;
    }
    int pos = ftell(f);
    printf("Initial position: %d\n", pos);
    fseek(f, 7, SEEK_SET());
    pos = ftell(f);
    printf("Position after seek: %d\n", pos);
    char *partial = fgets(f, 256);
    printf("Read after seek: %s", partial);
    fclose(f);
    printf("PASS: File positioning works\n");

    printf("Test 4: End of file detection\n");
    f = fopen("test_output.txt", "r");
    if (f == 0) {
        printf("ERROR: Could not open file\n");
        return 1;
    }
    int line_count = 0;
    while (feof(f) == 0) {
        char *line = fgets(f, 256);
        if (strlen(line) > 0) {
            line_count = line_count + 1;
        }
    }
    printf("Total lines read: %d\n", line_count);
    fclose(f);
    printf("PASS: EOF detection works\n");

    printf("Test 5: File rename operation\n");
    int result = frename("test_output.txt", "test_renamed.txt");
    if (result == 0) {
        printf("PASS: File renamed successfully\n");
    } else {
        printf("ERROR: File rename failed\n");
    }

    printf("Test 6: File removal\n");
    result = fremove("test_renamed.txt");
    if (result == 0) {
        printf("PASS: File removed successfully\n");
    } else {
        printf("ERROR: File removal failed\n");
    }

    printf("\n=== All File I/O Tests Completed ===\n");
    return 0;
}