Okay, so it's a bit kludgy :

enumhandles lists all open handles in current process (ie. enumhandles.exe)

enumhandles xx lists all open handles in process xx (decimal)
----------------------------------------------------------------------------
eh.c

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

WCHAR   *GetNameFromHandle(HANDLE h);       // eh2.c
WCHAR   *GetPipeFromHandle(HANDLE h);       // eh2.c
void     EnumLocalHandles();                // eh.c
void     EnumRemoteHandles(HANDLE process); // eh.c

void main(int argc, char *argv[])
{
    DWORD   pid;
    HANDLE  OtherProcess;

    if(argc==1)
    {
        printf("\n\nHandles for current process\n");
        printf("===========================\n");

        EnumLocalHandles();
    }
    else
    {
        pid=atol(argv[1]);

        OtherProcess=OpenProcess(PROCESS_DUP_HANDLE,
                                 FALSE,
                                 pid);

        if(OtherProcess==NULL)
        {
            printf("Can't open process %lu\n",pid);
            return;
        }

        printf("\n\nHandles for process %4lu\n",pid);
        printf("===========================\n");

        EnumRemoteHandles(OtherProcess);
        CloseHandle(OtherProcess);
    }
    printf("\n\n");
}

/*
EnumLocalHandles lists all the handles for the current process.
Because this is quite boring,  we open a file and a pipe first.
*/

void EnumLocalHandles()
{
/* Make something to look at */
    HANDLE h,p;
    DWORD i;
    DWORD  htype;

    h=CreateFile("E:\\MSDEV\\projects\\findmailslot\\enumhandle\\Debug\\eh2.obj",
                 GENERIC_READ,0,NULL,OPEN_EXISTING,0,NULL);

    p=CreateNamedPipe("\\\\.\\pipe\\MyPipe",
                      PIPE_ACCESS_DUPLEX,
                      PIPE_TYPE_MESSAGE,
                      PIPE_UNLIMITED_INSTANCES,
                      4096, 4096,1000,NULL);


    for(i=0;i<0x400;i+=4)  // Nasty hacky loop
    {
        htype=GetFileType((HANDLE)i);

        switch(htype)
        {
        case FILE_TYPE_UNKNOWN:
            break;
        case FILE_TYPE_DISK:
            printf("%03lx disk %ls\n",i,GetNameFromHandle((HANDLE)i));
           break;
        case FILE_TYPE_CHAR:
            printf("%03lx char\n",i);
            break;
        case FILE_TYPE_PIPE:
            printf("%03lx pipe %ls\n",i,GetNameFromHandle((HANDLE)i));
            break;
        }
    }

    CloseHandle(h);
    CloseHandle(p);
}

void EnumRemoteHandles(HANDLE process)
{
    HANDLE duplicate;
    DWORD  htype,i;

    for(i=0;i<0x400;i+=4)
    {
/*
Make a copy of their handle in our handle table.
*/

        if(DuplicateHandle(process,
                           (HANDLE)i,
                           GetCurrentProcess(),
                           &duplicate,
                           0,
                           FALSE,
                           DUPLICATE_SAME_ACCESS))
        {

            htype=GetFileType(duplicate);

            switch(htype)
            {
            case FILE_TYPE_UNKNOWN:
                break;
            case FILE_TYPE_DISK:
                printf("%03lx disk %ls\n",i,GetNameFromHandle(duplicate));
               break;
            case FILE_TYPE_CHAR:
                printf("%03lx char %ls\n",i,GetNameFromHandle(duplicate));
                break;
            case FILE_TYPE_PIPE:
                printf("%03lx pipe %ls\n",i,GetNameFromHandle(duplicate));
                break;
            } // switch

            CloseHandle(duplicate);

        } // if
    } // for
}

----------------------------------------------------------------------------
eh2.c

#define _X86_
#include <ntddk.h>    // and link with ntdll.lib
#include <stdio.h>
#include <ntstatus.h>

WCHAR   *GetNameFromHandle(HANDLE h)
{
    char            buffer[4096];
    IO_STATUS_BLOCK IoStatusBlock;
    NTSTATUS        status;

    memset(buffer,0,4096);

    status=ZwQueryInformationFile(h,
                                  &IoStatusBlock,
                                  buffer,
                                  4096,
                                  FileNameInformation);


   /*
    Returns

       {
           DWORD  length;
           WCHAR  name[];
       }

    */

    return((WCHAR*)(buffer+4));
}

----------------------------------------------------------------------------
Last updated 1st September '96

Personal jon@brilig.demon.co.uk

Work jedwards@drsolomon.com