How to enumerate all devices in Windows

 

In Linux, we can read/proc/partitions to obtain the names of all the hard disks and partitions in the system. However, in windows, how can we obtain the various devices in the system? Here we use the Windows API ---Findfirstvolume,

Findnextvolume
And
Findvolumeclose.

These APIs can enumerate various devices in windows.

 

The following program is taken from Microsoft's msdn example program to display the path names of all devices and volumes in the system. For each volume, the program in the example searches for each volume in the system, and the program obtains the device name and Path Name of the volume, and displays it.

 

 

# Include <windows. h> <br/> # include <stdio. h> <br/> void displayvolumepaths (<br/> _ in pwchar volumename <br/>) <br/>{< br/> DWORD charcount = max_path + 1; <br/> pwchar names = NULL; <br/> pwchar nameidx = NULL; <br/> bool success = false; <br/> (;;) <br/> {<br/> // allocate a buffer to hold the paths. <br/> names = (pwchar) New byte [charcount * sizeof (wchar)]; <br/> If (! Names) <br/>{< br/> // <br/> // If memory can't be allocated, return. <br/> return; <br/>}< br/> // <br/> // obtain all of the paths <br/> // For this volume. <br/> success = getvolumepathnamesforvolumenamew (<br/> volumename, names, charcount, & charcount <br/>); <br/> If (SUCCESS) <br/>{< br/> break; <br/>}< br/> If (getlasterror ()! = Error_more_data) <br/>{< br/> break; <br/>}< br/> // <br/> // try again with the <br/> // new suggested size. <br/> Delete [] names; <br/> names = NULL; <br/>}< br/> If (SUCCESS) <br/> {<br/> // display the varous paths. <br/> for (nameidx = names; <br/> nameidx [0]! = L'/0'; <br/> nameidx + = wcslen (nameidx) + 1) <br/>{< br/> wprintf (L "% s ", nameidx); <br/>}< br/> wprintf (L "/N"); <br/>}< br/> If (names! = NULL) <br/>{< br/> Delete [] names; <br/> names = NULL; <br/>}< br/> return; <br/>}< br/> void _ cdecl wmain (void) <br/>{< br/> DWORD charcount = 0; <br/> wchar devicename [max_path] = l ""; <br/> DWORD error = error_success; <br/> handle findhandle = invalid_handle_value; <br/> bool found = false; <br/> size_t Index = 0; <br/> bool success = false; <br/> wchar volumename [max_path] = l ""; <br/>/ /<Br/> // enumerate all volumes in the system. <br/> findhandle = findfirstvolumew (volumename, arraysize (volumename); <br/> If (findhandle = invalid_handle_value) <br/>{< br/> error = getlasterror (); <br/> wprintf (L "findfirstvolumew failed with error code % d/N", error ); <br/> return; <br/>}< br/> (;;) <br/>{< br/> // <br/> // skip //? /Prefix and remove the trailing backslash. <br/> Index = wcslen (volumename)-1; <br/> If (volumename [0]! = L' // '| <br/> volumename [1]! = L' // '| <br/> volumename [2]! = L '? '| <Br/> volumename [3]! = L' // '| <br/> volumename [Index]! = L' // ') <br/>{< br/> error = error_bad_pathname; <br/> wprintf (L "findfirstvolumew/findnextvolumew returned a bad path: % s/n ", volumename); <br/> break; <br/>}< br/> // <br/> // querydosdevicew doesn' t allow a trailing backslash, <br/> // so temporarily remove it. <br/> volumename [Index] = l'/0'; <br/> charcount = querydosdevicew (& volumename [4], devicename, arraysize (devicename )); <br/> volumenam E [Index] = l' // '; <br/> If (charcount = 0) <br/>{< br/> error = getlasterror (); <br/> wprintf (L "querydosdevicew failed with error code % d/N", error); <br/> break; <br/>}< br/> wprintf (L "/nfound a device:/n % s", devicename); <br/> wprintf (L "/nvolume Name: % s ", volumename); <br/> wprintf (L"/npaths: "); <br/> displayvolumepaths (volumename ); <br/> // move on to the next volume. <br/> succ ESS = findnextvolumew (findhandle, volumename, arraysize (volumename); <br/> If (! Success) <br/>{< br/> error = getlasterror (); <br/> If (error! = Error_no_more_files) <br/>{< br/> wprintf (L "findnextvolumew failed with error code % d/N", error); <br/> break; <br/>}< br/> // <br/> // finished iterating <br/> // through all the volumes. <br/> error = error_success; <br/> break; <br/>}< br/> findvolumeclose (findhandle ); <br/> findhandle = invalid_handle_value; <br/> return; <br/>}< br/>

 

The following is an example of program output. For each volume, output its volume device path, Volume guid path, and device characters.

Found a device:
 /Device/HarddiskVolume2
Volume name: //?/Volume{4c1b02c1-d990-11dc-99ae-806e6f6e6963}/
Paths:  C:/

Found a device:
 /Device/CdRom0
Volume name: //?/Volume{4c1b02c4-d990-11dc-99ae-806e6f6e6963}/
Paths:  D:/