Dealing with bitmask

[aamir121a]

Within Win32 API the is a function
getlogicaldrives returns a DWORD , as all logical drives on your system ,

reference here
http://msdn.microsoft.com/en-us/libr...=vs.85%29.aspx ,

it usage it some what cryptic , as it returns all drives as bit mask ,

could some explain what bit mask are and how to use them , as in get some meaning full data out of them.

[Alex F]

MSDN: Bit position 0 (the least-significant bit) is drive A, bit position 1 is drive B, bit position 2 is drive C, and so on.

DWORD mask = GetLogicalDrives();

if ( mask & (1 << 0) )
{
    // drive A is available
}

if ( mask & (1 << 1) )
{
    // drive B is available
}

if ( mask & (1 << 2) )
{
    // drive C is available
}

...