_getdiskfree
Populates a _diskfree_t structure with information about a disk drive.
unsigned _getdiskfree( unsigned drive, struct _diskfree_t * driveinfo );
If the function succeeds, the return value is zero. If the function fails, the return value is the error code. The value errno is set for any errors returned by the operating system. For more information about error conditions indicated by errno, see errno.
The _diskfree_t structure is defined in Direct.h.
struct _diskfree_t {
unsigned total_clusters;
unsigned avail_clusters;
unsigned sectors_per_cluster;
unsigned bytes_per_sector;
};
This function validates its parameters. If the driveinfo pointer is NULL or drive specifies an invalid drive, this function invokes an invalid parameter handler, as described in Parameter Validation. If execution is allowed to continue, the function returns EINVAL and sets errno to EINVAL. Valid drives range from 0 to 26. A drive value of 0 specifies the current drive; thereafter, numbers map onto letters of the English alphabet, so 1 indicates drive A, 3 indicates drive C, and so on.
Routine | Required header |
|---|---|
_getdiskfree | <direct.h> |
For more compatibility information, see Compatibility in the Introduction.
// crt_getdiskfree.c
// compile with: /c
#include <windows.h>
#include <direct.h>
#include <stdio.h>
#include <tchar.h>
TCHAR g_szBorder[] = _T("======================================================================\n");
TCHAR g_szTitle1[] = _T("|DRIVE|TOTAL CLUSTERS|AVAIL CLUSTERS|SECTORS / CLUSTER|BYTES / SECTOR|\n");
TCHAR g_szTitle2[] = _T("|=====|==============|==============|=================|==============|\n");
TCHAR g_szLine[] = _T("| A: | | | | |\n");
void utoiRightJustified(TCHAR* szLeft, TCHAR* szRight, unsigned uVal);
int main(int argc, char* argv[]) {
TCHAR szMsg[4200];
struct _diskfree_t df = {0};
ULONG uDriveMask = _getdrives();
unsigned uErr, uLen, uDrive;
printf(g_szBorder);
printf(g_szTitle1);
printf(g_szTitle2);
for (uDrive=1; uDrive<=26; ++uDrive) {
if (uDriveMask & 1) {
uErr = _getdiskfree(uDrive, &df);
memcpy(szMsg, g_szLine, sizeof(g_szLine));
szMsg[3] = uDrive + 'A' - 1;
if (uErr == 0) {
utoiRightJustified(szMsg+8, szMsg+19, df.total_clusters);
utoiRightJustified(szMsg+23, szMsg+34, df.avail_clusters);
utoiRightJustified(szMsg+38, szMsg+52, df.sectors_per_cluster);
utoiRightJustified(szMsg+56, szMsg+67, df.bytes_per_sector);
}
else {
uLen = FormatMessage(FORMAT_MESSAGE_FROM_SYSTEM, NULL,
uErr, 0, szMsg+8, 4100, NULL);
szMsg[uLen+6] = ' ';
szMsg[uLen+7] = ' ';
szMsg[uLen+8] = ' ';
}
printf(szMsg);
}
uDriveMask >>= 1;
}
printf(g_szBorder);
}
void utoiRightJustified(TCHAR* szLeft, TCHAR* szRight, unsigned uVal) {
TCHAR* szCur = szRight;
int nComma = 0;
if (uVal) {
while (uVal && (szCur >= szLeft)) {
if (nComma == 3) {
*szCur = ',';
nComma = 0;
}
else {
*szCur = (uVal % 10) | 0x30;
uVal /= 10;
++nComma;
}
--szCur;
}
}
else {
*szCur = '0';
--szCur;
}
if (uVal) {
szCur = szLeft;
while (szCur <= szRight) {
*szCur = '*';
++szCur;
}
}
}
====================================================================== |DRIVE|TOTAL CLUSTERS|AVAIL CLUSTERS|SECTORS / CLUSTER|BYTES / SECTOR| |=====|==============|==============|=================|==============| | A: | The device is not ready. | | | | C: | 4,721,093 | 3,778,303 | 8 | 512 | | D: | 1,956,097 | 1,800,761 | 8 | 512 | | E: | The device is not ready. | | | ======================================================================
Not applicable. To call the standard C function, use PInvoke. For more information, see Platform Invoke Examples.