emacsclientw

[Jason Rumney]

Have you tested the emacsclientw.exe build with MSVC?

I think there is also a need for something that starts Emacs if it is 
not already running, so I came up with the following (based on 
runemacs.c), which I intended to check into the nt directory. The 
intention is to use this to associate Emacs with file types in Explorer 
and other applications that allow external editors.


/* Copyright (C) 2006 Free Software Foundation, Inc.

This file is part of GNU Emacs.

GNU Emacs is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.

GNU Emacs is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with GNU Emacs; see the file COPYING.  If not, write to
the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
Boston, MA 02110-1301, USA.  */


/*
  Simple program to start emacsclient or emacs with its console window
  hidden.

  This program is provided for conveniently associating emacs with
  files in Windows Explorer and other GUI programs.

  */

#include <windows.h>
#include <string.h>
#include <malloc.h>

int launch_app(char *dir_name, char *app_name, LPSTR cmd_line)
{
  STARTUPINFO start;
  SECURITY_ATTRIBUTES sec_attrs;
  PROCESS_INFORMATION child;
  int wait_for_child = FALSE;
  DWORD priority_class = NORMAL_PRIORITY_CLASS;
  DWORD ret_code = 0;
  char *new_cmd_line;

  new_cmd_line = alloca (MAX_PATH + strlen (cmd_line) + 3);

  /* Quote executable name in case of spaces in the path.  */
  *new_cmd_line = '"';
  strcpy (new_cmd_line + 1, dir_name);

  strcat (new_cmd_line, "\\");
  strcat (new_cmd_line, app_name);
  strcat (new_cmd_line, "\" ");

  /* Append original arguments if any.  */
  strcat (new_cmd_line, cmd_line);

  memset (&start, 0, sizeof (start));
  start.cb = sizeof (start);
  start.dwFlags = STARTF_USESHOWWINDOW | STARTF_USECOUNTCHARS;
  start.wShowWindow = SW_HIDE;
  /* Ensure that we don't waste memory if the user has specified a huge
     default screen buffer for command windows.  */
  start.dwXCountChars = 80;
  start.dwYCountChars = 25;

  sec_attrs.nLength = sizeof (sec_attrs);
  sec_attrs.lpSecurityDescriptor = NULL;
  sec_attrs.bInheritHandle = FALSE;

  if (CreateProcess (NULL, new_cmd_line, &sec_attrs, NULL, TRUE, priority_class,
                     NULL, NULL, &start, &child))
    {
      WaitForSingleObject (child.hProcess, INFINITE);
      GetExitCodeProcess (child.hProcess, &ret_code);

      CloseHandle (child.hThread);
      CloseHandle (child.hProcess);
    }
  else
    ret_code = 1;

  return ret_code;
}

int WINAPI
WinMain (HINSTANCE self, HINSTANCE prev, LPSTR cmd_line, int show)
{
  char dir_name[MAX_PATH];
  char *p;

  /* Figure out what directory this is run from, so we can find the
     emacsclient and emacs executables.  */
  if (!GetModuleFileName (NULL, dir_name, MAX_PATH))
    goto error;
  if ((p = strrchr (dir_name, '\\')) == NULL)
    goto error;
  *p = 0;

  if ((launch_app (dir_name, "emacsclient.exe", cmd_line) == 0)
      || launch_app(dir_name, "emacs.exe", cmd_line) == 0)
    return 0;

 error:
  MessageBox (NULL, "Could not start Emacs", "Error", MB_ICONSTOP);
  return 1;
}