Accès direct aux fichiers en C++?

Question

Est-il possible d'écrire directement sur le disque sans cache en C++? Actuellement J'utilise:

int open(fileout, O_CREATE | O_WRONLY | O_DIRECT); 
FILE *fh = fdopen(fileout_dev, "wb"); 

Y at-il des bibliothèques de plates-formes croisées permettant de le faire?

Merci Arman.

Answer 1

Si vous parlez en mémoire tampon, vous pouvez utiliser setbuf ou setvbuf

/* setbuf example */ 
#include <stdio.h> 

int main() 
{ 
    char buffer[BUFSIZ]; 
    FILE *pFile1, *pFile2; 

    pFile1=fopen ("myfile.txt","w"); 
    pFile2=fopen ("myfile2.txt","a"); 

    setbuf (pFile1 , buffer); 
    fputs ("This is sent to a buffered stream",pFile1); 
    fflush (pFile1); 

    setbuf (pFile2 , NULL); 
    fputs ("This is sent to an unbuffered stream",pFile2); 

    fclose (pFile1); 
    fclose (pFile2); 

    return 0; 
} 


/* setvbuf example */ 
#include <stdio.h> 

int main() 
{ 
    FILE *pFile; 

    pFile=fopen ("myfile.txt","w"); 

    // _IONBF disables buffering 
    setvbuf (pFile , NULL , _IONBF, 0); 

    // File operations here 

    fclose (pFile); 

    return 0; 
}