list windows volume roots as `\0`-delimited cygwin paths

volumes.c

#include <windows.h>
#include <stdio.h>
#include <wchar.h>
#include <sys/cygwin.h>

/* based on the starting point
   https://learn.microsoft.com/en-us/windows/win32/fileio/displaying-volume-paths
 */
void main(void)
{
    DWORD  Error                = ERROR_SUCCESS;
    HANDLE FindHandle           = INVALID_HANDLE_VALUE;
    BOOL   Success              = FALSE;
    WCHAR  VolumeName[MAX_PATH] = L"";

    FindHandle = FindFirstVolumeW(VolumeName, ARRAYSIZE(VolumeName));

    if (FindHandle == INVALID_HANDLE_VALUE)
    {
        Error = GetLastError();
        fprintf(stderr, "FindFirstVolumeW failed with error code %d\n", Error);
        return;
    }

    do
    {
        DWORD  CharCount = MAX_PATH + 1;
        PWCHAR Names     = (PWCHAR) malloc(CharCount * sizeof(WCHAR));
        if ( !Names )
            return;

        while (!(Success = GetVolumePathNamesForVolumeNameW(
                VolumeName, Names, CharCount, &CharCount
                )) &&
               GetLastError() == ERROR_MORE_DATA &&
               (Names = (PWCHAR) realloc(Names, CharCount * sizeof(WCHAR))));

        if ( !Names )
            return;

        if ( Success )
        {
            for ( PWCHAR NameIdx = Names;
                  NameIdx[0] != L'\0';
                  NameIdx += wcslen(NameIdx) + 1 )
            {
                PCHAR cygpath = cygwin_create_path(CCP_WIN_W_TO_POSIX, NameIdx);
                // strlen + 1 to also output terminating NUL
                fwrite(cygpath, 1, strlen(cygpath)+1, stdout);
                free(cygpath);
            }
        }

        free(Names);
    } while (Success = FindNextVolumeW(FindHandle, VolumeName, ARRAYSIZE(VolumeName)));

    if ( !Success )
    {
        Error = GetLastError();

        if (Error != ERROR_NO_MORE_FILES)
            fprintf(stderr, "FindNextVolumeW failed with error code %d\n", Error);
    }

    FindVolumeClose(FindHandle);
    return;
}