Linux. Not printing to file

Question

i'm just coding module for HLDS server extension metamod. I wrote a simple utility function for writing logs in format %LOGNAME%_%DATE%.log In windows that function is working fine, but in linux it create file but write nothing. First I try to search information about that, but I do not found a solution. I try to fflush file handle, set buffer to _IONBF mode, but nothing is helping. Thank you very much for reading this and helping me with that problem.

void UTIL_LogToFile(char* szFileName, const char *fmt, ...)
{
va_list     argptr;
va_start ( argptr, fmt );
vsnprintf ( g_szLogString, sizeof(g_szLogString), fmt, argptr );
va_end   ( argptr );

char* szFilePath = new char[strlen(GlobalVariables::g_szDLLDirPath) + 12 + 30 + 1];
char* szLogFile = get_timestring("_%Y%m%d.log");
sprintf(szFilePath, "%slogs/%s%s", (GlobalVariables::g_szDLLDirPath), szFileName, szLogFile);
FILE* hFile = fopen(szFilePath, "a+");
delete[] szFilePath;
delete[] szLogFile;
if(hFile == NULL)
{
    char szError[256];
    sprintf(szError, "Error fopen: %s\n", strerror(errno));
    SERVER_PRINT(szError);
    clearerr(hFile);
    return;
}

fprintf(hFile, g_szLogString);
if(ferror(hFile))
{
    char szError[256];
    sprintf(szError, "Error fprintf: %s\n", strerror(errno));
    SERVER_PRINT(szError);
    clearerr(hFile);
    return;
}
fclose(hFile);

}

Answer 1

You should only check errno if and only if the previous function failed.

If the previous call didn't fail the value of errno is undefined .

So to properly check for errors you must first check if the fopen call returned a null pointer:

FILE* hFile = fopen(szFilePath, "a+");
if (hFile == nullptr)
{
    perror(szFilePath);
    return;
}

Answer 2

其他功能出错：更改了源代码： https : //github.com/In-line/metamod_unprecacher/commit/08b2fabd03f838bee62913b0d2a4f4a4bbf1e6df