Platform SDK: DLLs, Processes, and Threads

LoadModule

The LoadModule function loads and executes an application or creates a new instance of an existing application.

Note  This function is provided only for compatibility with 16-bit versions of Windows. Win32-based applications should use the CreateProcess function.

DWORD LoadModule(
  LPCSTR lpModuleName,      // file name of application
  LPVOID lpParameterBlock   // parameter block 
);

Parameters

lpModuleName
[in] Pointer to a null-terminated string that contains the file name of the application to run. When specifying a path, be sure to use backslashes (\), not forward slashes (/). If the lpModuleName parameter does not contain a directory path, the system searches for the executable file in this order:
  1. The directory from which the application loaded.
  2. The current directory.
  3. Windows 95/98: The Windows system directory. Use the GetSystemDirectory function to get the path of this directory.

    Windows NT/ 2000: The 32-bit Windows system directory. Use the GetSystemDirectory function to get the path of this directory. The name of this directory is SYSTEM32.

  4. Windows NT/ 2000: The 16-bit Windows system directory. There is no Win32 function that obtains the path of this directory, but it is searched. The name of this directory is SYSTEM.
  5. The Windows directory. Use the GetWindowsDirectory function to get the path of this directory.
  6. The directories that are listed in the PATH environment variable.
lpParameterBlock
[in] Pointer to an application-defined LOADPARMS32 structure that defines the new application's parameter block.

The LOADPARMS32 structure has the following form:

typedef struct tagLOADPARMS32 { 
    LPSTR lpEnvAddress;  // address of environment strings 
    LPSTR lpCmdLine;     // address of command line 
    LPSTR lpCmdShow;     // how to show new program 
    DWORD dwReserved;    // must be zero 
} LOADPARMS32; 
Member Description
lpEnvAddress Pointer to an array of null-terminated strings that supply the environment strings for the new process. The array has a value of NULL as its last entry. A value of NULL for this parameter causes the new process to start with the same environment as the calling process.
lpCmdLine Pointer to a Pascal-style string that contains a correctly formed command line. The first byte of the string contains the number of bytes in the string. The remainder of the string contains the command line arguments, excluding the name of the child process. If there are no command line arguments, this parameter must point to a zero length string; it cannot be NULL.
lpCmdShow Pointer to a structure containing two WORD values. The first value must always be set to two. The second value specifies how the application window is to be shown and is used to supply the wShowWindow member of the STARTUPINFO structure to the CreateProcess function. See the description of the nCmdShow parameter of the ShowWindow function for a list of acceptable values.
dwReserved This parameter is reserved; it must be zero.

Set all unused members to NULL, except for lpCmdLine, which must point to a null-terminated string if it is not used.

Return Values

If the function succeeds, the return value is greater than 31.

If the function fails, the return value is an error value, which may be one of the following values.

Value Meaning
0 The system is out of memory or resources.
ERROR_BAD_FORMAT The .exe file is invalid (non-Win32 .exe or error in .exe image).
ERROR_FILE_NOT_FOUND The specified file was not found.
ERROR_PATH_NOT_FOUND The specified path was not found.

Remarks

Win32-based applications should use the CreateProcess function. In the Win32 API, the implementation of the LoadModule function calls CreateProcess. The following table shows how each parameter for CreateProcess is formed.

CreateProcess parameter Value
lpszApplicationName lpModuleName
lpszCommandLine lpParameterBlock->lpCmdLine
lpProcessAttributes NULL
lpThreadAttributes NULL
bInheritHandles FALSE
dwCreationFlags 0
lpEnvironment lpParameterBlock->lpEnvAddress
lpCurrentDirectory NULL
lpStartupInfo The structure is initialized to zero. The cb member is set to the size of the structure, and the wShowWindow member is set to the value of the second word of the LoadModule lpParameterBlock->lpCmdShow parameter.
lpProcessInformation.hProcess The handle is immediately closed.
lpProcessInformation.hThread The handle is immediately closed.

Requirements

  Windows NT/2000: Requires Windows NT 3.1 or later.
  Windows 95/98: Requires Windows 95 or later.
  Header: Declared in Winbase.h; include Windows.h.
  Library: Use Kernel32.lib.

See Also

Dynamic-Link Libraries Overview, Dynamic-Link Library Functions, CreateProcess, GetSystemDirectory, GetWindowsDirectory, ShowWindow, STARTUPINFO, WinExec