问我能确保，当fopen()为"w“打开一个文件时，程序不会创建文件吗？-ing()

EN

void 
gather_input (char* infileName, char* outfileName, char* mode,
          FILE* inputFile, FILE* outputFile)
{   int flag = 0; //error checking flag
do
{   flag = 0;
    printf("Enter the name of the source file: "); 
    scanf("%s", infileName);
    if (!(inputFile = open_input_file(infileName))) //will enter if statement only if
    {   fprintf(stderr, "Error opening '%s': %s\n", //inputFile == NULL
        infileName, strerror(errno)); //some error checking
        flag = 1; //true
    }
} while (flag);

do
{   flag = 0;
    printf ("Enter the name of the destination file: ");
    scanf("%s", outfileName);
    if (!(outputFile = open_output_file(outfileName)))
    {   fprintf (stderr, "Error opening '%s': %s\n",
        infileName, strerror(errno));
        flag = 1;
    }
} while (flag);