command line options in winmain with __argv

[eric dexter]

I want to compare what I get on the command line in winmain with an if statement.. I am getting a beginers error but I don't have an example to use to fix it.. cannot convert from 'const int' to 'char *' in this line if (__argv[1] = 'file'){};
I am very lost with this error and any help would be apreaceated

int WINAPI WinMain(HINSTANCE hInstance, //handle to current instance
                   HINSTANCE hPrevInstance, //pointer to the previous instance
                   LPSTR lpCmdLine,  //pointer to the command file
                   int nCmdShow)     //show state of the window
{
    //
 
    HWAVEOUT hWaveOut;  //handle to sound card output
    WAVEFORMATEX WaveFormat;  //The sound format
    WAVEHDR WaveHeader;       //Wave header for our sound data
 
    char Data[BUFFERSIZE];  //sound data buffer
 
    HANDLE Done;  // Event handle that tells us the sound has finished being played.
                  // This is a real efficient way to put the program to sleep
                    //The sound card is processing the sound buffer
 
    double x;
    int ii;
    int i;
    int FREQUENCY;
    FILE * pFile; //this is set up to read from a file
    char string [100]; //this is the file we are reading
    struct wordd line[20]; //create an array of 20 words
    char * pch; //from strtok example
 
 
    //if command line is file
    if (__argv[1] == "file")
    {
 
          pFile = fopen (__argv[2] , "r"); //second argument is filename
          if (pFile == NULL) perror ("Error opening file");
          else {
              fgets (string , 100 , pFile); //get a line from a file
              pch = strtok (string," "); //split string into token seperated by a space
              i = 0; // iterator starts at 0
              while (pch != NULL) // while there is something to split 
              {
                  i++; //this indicates where you are in the loop not used here but for more advanced synths
            //      line[i].word = pch; //put pch in place in the line for this synth freq is first word
                  ii = atoi(pch);
                  pch = strtok (NULL, " "); //grab next word
                  //I will need to have an array of pch to do more paremeters in a synth..  redo the line maybe..
                  playsound(ii);
              }
              //ii = atoi(pch); //convert line to a number using atoi
             // playsound(ii);      //play the sound..
 
 
              //puts (string); prints line I think
              fclose (pFile);
 
   }
 
}
    if (__argv[1] = 'file'){};
         //playsound(int freq)}
    if (isdigit(__argv[1][1])) //if this is a number play the frequency
    {
         i = atoi(__argv[1]);
         playsound(i);
    }
    //if 
    //string  = __argv[1];
    //if (__argv[1] = 'file'){};
 
//** Release our event handle **
 
 return FALSE;
 
}
 
 

[weaknessforcats]

WinMain() is not main().

There is no command line in a Windows program and the arguments on the command line have to be fetched using GetCommandLine( ).

All that argc argv stuff is for native language console applications only.

[eric dexter]

It seems to compile fine and one of the if's is working it is when I look for a string instead of a charecter it complains.. is there an example of the other somewhere where I compare what I get with your command??? I saw that but didn't understand how to use it (no good examples)

[weaknessforcats]

You may need to post your revised code.

GetCommandLine( ) returns an LPTSTR, which is a char* if you are using ASCII and a wchar_t* if you are using Unicode.

Various C functions have been rewritten for Unicode. When you have your peoject set for ASCII you want the ANSI C version and for Unicode you want the ANSI C wide character version. You switch between these two by using the TCHAR mappings (Please read up on this).

The function mappings are http://msdn2.microsoft.com/en-us/library/ms860358.aspx.

[Banfa]

I want to compare what I get on the command line in winmain with an if statement.. I am getting a beginers error but I don't have an example to use to fix it.. cannot convert from 'const int' to 'char *' in this line if (__argv[1] = 'file'){};
I am very lost with this error and any help would be apreaceated

int WINAPI WinMain(HINSTANCE hInstance, //handle to current instance
                   HINSTANCE hPrevInstance, //pointer to the previous instance
                   LPSTR lpCmdLine,  //pointer to the command file
                   int nCmdShow)     //show state of the window
{
<snipped>
 return FALSE;
 
}
 
 

The command line is accessable directly in WinMain via the lpCmdLine function argument. I do not think using __argc and __argp is a good idea, I do not believe these are documented/supported features. Thatis you have no guarantee that they will continue to exist from 1 version of the SDK to the next.

[weaknessforcats]

You can also create a Windows Console application and that will generate an _tmain(int argc, _TCHAR* argv[]).

Also note that using lpCmdLine does not retrieve the entire command line but only the first argv* portion. The type of lpCmdLine is a LPSTR so you can have only one argument. Usually, this is a file name to be read in that contains the other arguments.

If you are using Unicode, then you have to use GetCommandLine( ). There is a CommandLineToAr gvW() that you can use to recreate the argv string array.

[Banfa]

Also note that using lpCmdLine does not retrieve the entire command line but only the first argv* portion. The type of lpCmdLine is a LPSTR so you can have only one argument. Usually, this is a file name to be read in that contains the other arguments.

This is not true, the lpCmdLine is the entire command line concatinated into a single string excluding what would be in argv[0] (i.e. the program name).

Try this program with multiple command line arguments

#include "windows.h"
 
int APIENTRY WinMain(HINSTANCE hInstance,
                     HINSTANCE hPrevInstance,
                     LPSTR     lpCmdLine,
                     int       nCmdShow)
{
    MessageBox(NULL, lpCmdLine, "Command Line", MB_OK);
 
    return 0;
}
 

The difference between lpCmdLine and GetCommandLine is that lpCmdLine is type LPSTR (for historical reasons) where as lpCmdLine returns LPTSTR. This means that lpCmdLine is always a string of ASCII characters, but GetCommandLine can return a unicode string in a unicode enabled application.

[weaknessforcats]

I stand corrected. But:

#include "windows.h"

int APIENTRY WinMain(HINSTAN CE hInstance,
HINSTANCE hPrevInstance,
LPSTR lpCmdLine,
int nCmdShow)
{
MessageBox(NULL , lpCmdLine, "Command Line", MB_OK);

return 0;
}


The difference between lpCmdLine and GetCommandLine is that lpCmdLine is type LPSTR (for historical reasons) where as lpCmdLine returns LPTSTR. This means that lpCmdLine is always a string of ASCII characters, but GetCommandLine can return a unicode string in a unicode enabled application.

The MessageBox line only works with 16-bit Windows. MessageBox today is a macro that switches between MessageBoxA (ASCII) and MessageBoxW (Unicode). By default Windows programs are Unicode. That means you need the TCHAR mapping for this to compile. The code should be:

MessageBox(NULL, GetCommandLine(), TEXT("Command Line"), MB_OK);
 

You can't use lpCmdLine since this is always ASCII. For Unicode you would need to convert this to a Unicode string before passing it to MessageBox. Therefore, the current advice is to always use GetCommandLine( ).

Also, I think there is a typo in your reply:

where as lpCmdLine returns LPTSTR.

I think you mean to say:

whereas GetCommandLine( ) returns a LPTSTR.

[Banfa]

Also, I think there is a typo in your reply:

I think you mean to say:

whereas GetCommandLine( ) returns a LPTSTR.

Yes I did, my sloppy writing and coding aside I was just making the point that lpCmdLine points to the entire command line, but is a pointer to an ASCII string.

[eric dexter]

I saw this as an example. I haven't figured out how to split the line to get an array of what is on the command line (or if it is doing that how it is being done)

void CCommandLineDlg::OnBtnCmdLine() 
{
    // TODO: Add your control notification handler code here
    char CmdLine[80];
    char CmdResult[80];
 
    strcpy(CmdLine, GetCommandLine());
    sprintf(CmdResult, "%s", CmdLine);
    m_CommandLine.Format("%s", CmdResult);
 
    UpdateData(FALSE);
}
 

this is from
http://www.functionx.com/visualc/Lesson06.htm