VARARG PEEK

Function : Extension Manager

VARARG_PEEK - Peek at an argument from a variable argument list (no advance).

#include <global.h>
<type> VARARG_PEEK(

    VARARG_PTR  ap,
    <type>  Type);

Description :

Retrieve a value from a variable argument list, but do not advance the argument list pointer. This function is implemented as a macro.

A pointer into a variable argument list is declared using the macro VARARG_PTR and initialized using the VARARG_START() macro. Retrieving data from the variable argument list with VARARG_GET() will update the argument list pointer to point to the next argument, while retrieving the value using VARARG_PEEK() will obtain the value without updating the argument list pointer. The argument type information is used to determine how large the argument value is, and is used in a typecast to ensure that assignment of the value is correct.

Parameters : Input : ap - Current pointer into the variable argument list.

Type - This must be a valid elementary data type. Some examples of elementary data types are "int", "WORD", "char", "DWORD", "char *", or "BOOL".

Output : (routine) - The type of the return value is specified by the "Type" argument.

Sample Usage :

void far cdecl SampleRoutine (
    char *String,
    WORD LastNamedArgument, ...)
{
DWORD temp1;
WORD  temp2;
VARARG_PTR ap;

VARARG_START(ap,LastNamedArgument);
        /* Start out just past last named argument */
temp1 = VARARG_GET(ap,DWORD);
        /* Get next DWORD into temp1 and advance */
temp2 = VARARG_PEEK(ap,WORD);
        /* Peek at next WORD, but no advance */
temp2 = VARARG_GET(ap,WORD);
        /* Get next WORD into temp2 and advance */
}