Get letter drives

im trying to get each drive on my computer. Is their a way to do this? Right now im just having it loop through four times for each drive on my computer but i want it to be portable for other computers with more or less drives.

Code:

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char buff[10];
int i;

for(i=0;i<4;i++){

GetLogicalDriveStrings(10,buff);

MessageBox(NULL,buff,"dd",MB_OK);
}

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this only return "A:/ "four times though.
thanks

Code:

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#include <windows.h>
#include <math.h>
#include <stdio.h>

BOOL is_drive(char letter, unsigned long drives) {
    return drives & (unsigned long)pow(2, letter - 'A');
}

int main(void) {
    unsigned long drvspec = GetLogicalDrives();

    for(char i = 'A'; i <= 'Z'; ++i) {
        if(is_drive(i, drvspec)) {
            printf("Drive %c\n", i);
        }
    }

    return 0;
}

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Parksie, do you mind explaining breifly how that works. Thanks

GetLogicalDrives returns an unsigned long (DWORD), where drive A is bit 0, drive B is bit 1, etc.

If they're set, the drive exists. So what that does is just to check through all of them seeing if the corresponding bit is set. I suppose I could drop the call to pow and use a shift (quicker, but I can't remember which way round it is for Intel).

im not sure why but I get a illegal operation whenI try and run it.

Works fine for me...

sorry, your code was right but here was the problem.

Code:

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SendMessage(drvlstS,LB_ADDSTRING,0,(LPARAM)i);

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do you know why I can't set that string?

Because i is only a single character.

Code:

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char buf[2] = { i, 0 };

SendMessage(drvlstS,LB_ADDSTRING,0,(LPARAM)buf);

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Thanks alot Parksie!

No probs :)

Oh yeah, anything that goes into that function must be upper case or it won't work.

Another version of parksies function:

PHP Code:

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// add this include
#include <ctype.h>
// and for debug purposes
#include <assert.h>

BOOL is_drive(char letter, unsigned long drives) {
    assert(isalpha(letter));
    return drives & (1 << (toupper(letter) - 'A'));
} 


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I'm pretty sure that left shift is right, but you must try. If it doesn't work correctly, try
0x80000000 >> (toupper(letter) - 'A')
or stick to parksies way.