How to check if exe is available from the server

Question

This is a client server application. I am creating an updater that will replace the list of exe files, run the scripts and all that needs to be updated. This will be installed on the server.

First I need to check if the executable opens through a network share. I can do this manually by going to the "Computer Management" section, then "General Files" and "Open Files". This seems to be the only way to check if the file is open. I tried using R / W to check if the file is open, but this did not work. Looked at Win32_ServerConnection, but it just listed the number of files that were open, not the names.

I would like to code this in Delphi 7 or C # if this cannot be done in Delphi. I found several programs that can view open files on the server, but cannot do anything.

Answer 1

​​, , . "" fName, ( ) . , . filessytem ( ). , Handle , - .

, .

 function IsFileInUse(fName: string): boolean;
  var
    HFileRes: HFILE;
  begin
    Result := false;
    if not FileExists(fName) then
      exit;
    HFileRes := CreateFile(pchar(fName),
      GENERIC_READ or GENERIC_WRITE,
      0, nil, OPEN_EXISTING,
      FILE_ATTRIBUTE_NORMAL,
      0);
    Result := (HFileRes = INVALID_HANDLE_VALUE);
    if not Result then
      CloseHandle(HFileRes);
  end;

Answer 2

? , . , .

Answer 3

Windows 2000 API NetFileEnum:

program test;

{$APPTYPE CONSOLE}

uses
  Windows,
  Classes,
  SysUtils;

type
  PFileInfo3 = ^TFileInfo3;
  TFileInfo3 = record
    fi3_id: DWORD;
    fi3_permissions: DWORD;
    fi3_num_locks: DWORD;
    fi3_pathname: PWideChar;
    fi3_username: PWideChar;
  end;

  TNetFileEnumCallback = function(const FileInfo: TFileInfo3; Data: Pointer): Boolean;

const
  netapi = 'netapi32.dll';

function NetApiBufferFree(Buffer: Pointer): DWORD; stdcall; external netapi;
function NetFileEnum(servername: PWideChar; basepath: PWideChar; username: PWideChar; level: DWORD; var bufptr: Pointer;
  prefmaxlen: DWORD; var entriesread: DWORD; var totalentries: DWORD; resume_handle: PDWORD): DWORD; stdcall;
  external netapi;

procedure EnumNetFileUsers(const LocalPath: WideString; Callback: TNetFileEnumCallback; Data: Pointer = nil);
const
  EntryCount = 32;
var
  NetResult, EntriesRead, TotalEntries, ResumeHandle: Cardinal;
  Buf: Pointer;
  P: PFileInfo3;
  I: Integer;
begin
  EntriesRead := 0;               
  TotalEntries := 0;
  ResumeHandle := 0;
  repeat
    NetResult := NetFileEnum(nil, PWideChar(LocalPath), nil, 3, Buf, EntryCount * SizeOf(TFileInfo3), EntriesRead,
      TotalEntries, @ResumeHandle);
    if not (NetResult in [ERROR_SUCCESS, ERROR_MORE_DATA]) then
      RaiseLastOSError(NetResult);
    try
      P := Buf;
      for I := 0 to EntriesRead - 1 do
      begin
        if Callback(P^, Data) then
          Break;

        Inc(P);
      end;
    finally
      NetApiBufferFree(Buf);
    end;
  until NetResult = ERROR_SUCCESS;
end;

function ShowFileInfo(const FileInfo: TFileInfo3; Data: Pointer): Boolean;
begin
  Result := False;
  Writeln(Format('id: %d, permissions: $%.8x, num_locks: %d, pathname: ''%s'', username: ''%s''',
    [FileInfo.fi3_id, FileInfo.fi3_permissions, FileInfo.fi3_num_locks, FileInfo.fi3_pathname, FileInfo.fi3_username]));
end;

begin
  try
    if ParamCount = 1 then
      EnumNetFileUsers(ParamStr(1), ShowFileInfo);
  except
    on E: Exception do
    begin
      Writeln(Format('[%s] %s', [E.ClassName, E.Message]));
      ExitCode := 1;
    end;
  end;
end.

, , LocalPath, , :

test.exe C:\\Dev\Test\test.exe

( ):

id: -469761405, permissions: $00000001, num_locks: 0, pathname: 'C:\\Dev\Test\test.exe', username: 'Ondrej'

, MSDN :

" NetFileEnum ".

Answer 4

"", , , . .

string name = Environment.MachineName;
string name = System.Net.Dns.GetHostName();
string name = System.Windows.Forms.SystemInformation.ComputerName;

Process[] myProcesses = Process.GetProcessesByName("myExeProcName",MachineName);
foreach(Process myProcess in myProcesses)
{
    Console.Write("MachineName : " + myProcess.MachineName + "\n");
}

Answer 5

FileSystemWatcher System.IO?

http://msdn.microsoft.com/en-us/library/system.io.filesystemwatcher.aspx