I can't figure out what is happening in my program, it's a simple function to clear all the Windows '\r' from a file, putting all the chars in another file and then rename it to substitute the old file. Every time I execute the function the rename() and remove() functions give me "Permission error" even if I had all the file pointers closed and the file on my PC is closed in every program. Here's the code

static bool correctFile(string fileName) {
        string name = fileName;
        FILE* test = fopen(fileName.c_str(), "rb");
        FILE *in, *out;
        char stringTest[1000];
        bool isWinFile = false;
        if (!test) {
            return false;
        }
        fread(stringTest, 1, 1000, test);
        fclose(test);
        for (size_t i = 0; i < strlen(stringTest) && !isWinFile; i  ) {
            if (stringTest[i] == '\r') {
                isWinFile = true;
            }
        }
        if (isWinFile) {
            in = fopen(fileName.c_str(), "rb");
            string tempFile = name   ".temp";
            out = fopen(tempFile.c_str(), "wb");
            if (!in || !out) {
                return false;
            }
            char temp;
            while (fread(&temp, sizeof(temp), 1, in) > 0) {
                if (temp != '\r') {
                    fwrite(&temp, sizeof(temp), 1, out);
                }
            }
            fclose(in);
            fclose(out);
            if (std::remove(fileName.c_str())) {
                std::cerr << "Error: " << strerror(errno);
                return false;
            }
            if (std::rename(tempFile.c_str(), fileName.c_str())) {
                return false;
            }
        }
        return true;
    }

If you find an error in this please tell me, thanks

CodePudding user response：

I found out that the old file and the new file must not be in the same folder for some reason

CodePudding user response：

Disable the virus scanner and see if the problem persists. Some antivirus products block access to files for a couple of microseconds after they have been written or modified. I know of Kaspersky for example.

I have a "Antivirus" retry loop in some of my batch files because of this. So one (ugly) solution is to retry the rename/remove operations a couple of times.