API, LOST... help

I am so confused.
Im trying to get the hang of win 32 api but im lost so far.
take this for example.


BOOL GetComputerName(
LPTSTR lpBuffer, // computer name
LPDWORD lpnSize // size of name buffer
);

BOOL I know returns true or false (1,0)
But what do I declare lpBuffer and lpnSize with ?

I see alot of API using these unknown(to me) data types.

Do I just LPTSTR mybuf[20];
and LPDWORD max = 21; ?????

Really lost, please help me get the hang of this.

Thanks

And something simple like this isnt even working.
BOOL LockWorkStation(VOID);


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


int main() {

LockWorkStation();
return 0;

}


This errors and says


C:\crap\test.cpp(10) : error C2065: 'LockWorkStation' : undeclared identifier

Any one ?

I'm not sure about LockWorkStation...I think it's one of those things you can't use on Win9x, so if you're compiling on a 9x platform it won't work anyway...


With GetComputerName() it's quite simple...

char compName[20];
GetComputerName(name, 20);


LPTSTR = Long Pointer To a String (If I'm not mistaken); most of the time you can just use a char* here.
LPDWORD = Long Pointer to a DWORD. DWORD is a double-word, but you can just use an int....

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

int main()

{

char cname[20];
GetComputerName(cname,20);
printf("Computer name = %s\n",cname);

return 0;
}

Error:

C:\crap\test.cpp(9) : error C2664: 'GetComputerNameA' : cannot convert parameter 2 from 'const int' to 'unsigned long *'
Conversion from integral type to pointer type requires reinterpret_cast, C-style cast or function-style cast
Error executing cl.exe.

And for lockworkstation im running 2k (NT) so it should work.

so type cast, my man.

Quote:

---

BOOL GetComputerName
(
LPTSTR lpBuffer, // computer name
LPDWORD lpnSize // size of name buffer
);

---

int main()
{
TCHAR cBuffer[50];
DWORD dwSize = 50;

if( GetComputerName( cBuffer, &dwSize ) )
{
printf( "%s %d\n", cBuffer, dwSize );
}
else
{
printf( "Error" );
}

return 0;
}



LPSTR is char*
LPTSTR is TCHAR*
LPCTSTR is const TCHAR*