OpenEuphoria

Re: [WIN] GetLogicalDrives returns drives NOT present

• Posted by CChris <christian.cuvier at agr?cultur?.gouv.fr> Jan 29, 2008
• 1134 views

Dan Moyer wrote:
> 
> Dan Moyer wrote:
> > 
> > <<SNIP>>
> > > > 
> > > > Chris: 
> > > > I kinda thought *logical* drives might be at least part of the problem
> > > > I'm
> > > > having, but I don't think I can decipher/translate the C code.  I'm
> > > > wondering if there isn't some way to defeat the presentation of the
> > > > error
> > > > messages?  I thought there is something along those line in Win32Lib?
> > > > 
> > > 
> > > If what you get is a dialog box that allows you to continue executing
> > > (yes/no/cancel),
> > > then calling setWarning(0) before running your code will suppress it. I
> > > must
> > > say that it is not the recommended way...
> > > 
> > > I'll try to find some time to post a translation of the code at MSDN.
> > > Actually,
> > > it's pretty simple: get all known volume strings, then retrieve all the
> > > paths
> > > for each of those strings. Because there are sequences of chars
> > > everywhere,
> > > the code isn't as short as you might exect at first, but... it may be
> > > worth
> > > to try again.
> > > 
> > > </snip>
> > > 
> > > CChris
> > 
> > CChris,
> > 
> > Thanks, but never mind, I found a "getVolumeInformation()" function
> > in a set of includes by Austin Cathey in my system, although I haven't yet
> > re-found it in contributions, where I must have got it from at some time.
> > 
> > That's pretty much what you originally suggested I do!  :)
> > 
> > Thanks for the effort, though.
> > 
> > Dan
> 
> Oops, the "getVolumeInformation" was really by William Heimbigner, it used a
> dll handling include that was by Austin Cathey, that's what confused me,
> I thought they were both by the same person. 
> 
> Dan

Try running this under exwc.exe, it works under XP Pro at work. No errors, hence
no error handling. Lines may wrap:

include dll.e
include machine.e
constant k32=open_dll("kernel32.dll")
if not k32 then 
crash_message("Couldn't find kernel32.dll; perhaps not running under
    Windows.")
    abort(1)
end if
constant
glds=define_c_func(k32,"GetLogicalDriveStringsA",{C_LONG,C_POINTER},C_LONG)
if glds=-1 then
crash_message("The GetLogicalDriveStringsA API is available only under Win
    2K Pro, XP or later")
    abort(1)
end if
constant all_string_sizes = c_func(glds,{0,0})
if not all_string_sizes then
    crash_message("GetLogicalDriveStringsA failed for some reason.")
    abort(1)
end if

-- retrieve all volume names
atom void
atom string_buffer string_buffer = allocate(all_string_sizes)
void = c_func(glds,{all_string_sizes,string_buffer})
if not void then
    crash_message("GetLogicalDriveStringsA failed for some reason.")
    abort(1)
end if
constant strlen = define_c_func(k32,"lstrlenA",{C_POINTER},C_LONG)
if strlen=-1 then
crash_message("lstrlen could not be found. Perhaps this is an Unicode build
    of Windows.")
    abort(1)
end if

puts(1,"Known drives:\n")
puts(1,repeat('=',13)&"\n\n")
-- scan all volumes
integer len_str
while 1 do -- read array of volume names
    -- how long is the volume string?
    len_str = c_func(strlen,{string_buffer})
    if not len_str then -- reached the end
        exit
    end if

    puts(1,peek({string_buffer,len_str})&"\n")

    -- next
    string_buffer += len_str+1

end while
?machine_func(26,0)

It gives me all available drives, some of them being mapped network drives, not
listing the CD-ROM drive where there's no cd, not listing USB ports with nothing
connected to it.

CChris