Parses a Unicode command line string and returns an array of pointers to the command line arguments, along with a count of such arguments, in a way that is similar to the standard C run-time argv and argc values.

Syntax

LPWSTR *CommandLineToArgvW(      
    LPCWSTR lpCmdLine,
    int *pNumArgs
);

Parameters

lpCmdLine

[in] 

Pointer to a null-terminated Unicode string that contains the full command line. If this parameter is an empty string the function returns the path to the current executable file.

pNumArgs

[out] Pointer to an int that receives the number of array elements returned, similar to argc.

Return Value

A pointer to an array of LPWSTR values, similar to argv.

If the function fails, the return value is NULL. To get extended error information, call GetLastError.

Remarks

The address returned by CommandLineToArgvW is the address of the first element in an array of LPWSTR values; the number of pointers in this array is indicated by pNumArgs. Each pointer to a null-terminated Unicode string represents an individual argument found on the command line.

CommandLineToArgvW allocates a block of contiguous memory for pointers to the argument strings, and for the argument strings themselves; the calling application must free the memory used by the argument list when it is no longer needed. To free the memory, use a single call to the LocalFree function.

For more information about the argv and argc argument convention, see Argument Definitions and Parsing C++ Command-Line Arguments.

The GetCommandLineW function can be used to get a command line string that is suitable for use as the lpCmdLine parameter.

This function accepts command lines that contain a program name; the program name can be enclosed in quotation marks or not.

CommandLineToArgvW has a special interpretation of backslash characters when they are followed by a quotation mark character ("), as follows:

• 2n backslashes followed by a quotation mark produce n backslashes followed by a quotation mark.
• (2n) + 1 backslashes followed by a quotation mark again produce n backslashes followed by a quotation mark.
• n backslashes not followed by a quotation mark simply produce n backslashes.

Example

The following example demonstrates how to parse a Unicode command-line string. The code frees the memory for the argument list at exit.

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

int __cdecl main()
{
   LPWSTR *szArglist;
   int nArgs;
   int i;

   szArglist = CommandLineToArgvW(GetCommandLineW(), &nArgs);
   if( NULL == szArglist )
   {
      wprintf(L"CommandLineToArgvW failed\n");
      return 0;
   }
   else for( i=0; i<nArgs; i++) printf("%d: %ws\n", i, szArglist[i]);

// Free memory allocated for CommandLineToArgvW arguments.

   LocalFree(szArglist);

   return(1);
}

Function Information

Minimum DLL Version	Shell32.dll version 6.0 or later
Custom Implementation	No
Header	Shellapi.h
Import library	Shell32.lib
Minimum operating systems	Windows NT Workstation 3.5, Windows NT Server 3.5, Windows 2000 Professional, Windows 2000 Server, Windows XP, Windows Server 2003
Unicode	Implemented as Unicode version.