Thread: Variable Argument List Passing

So I'm abusing C++ in strange and wonderful ways, and I want to write a function like this:

Code:

void Log(char *filename, char *str, ...);

This function would open a file specified by filename and then call printf in the following sort of fashion:

Code:

fprintf(fp,str, ...);

The idea is to create a function that loads up a log file, printf's the stuff from str and ... to the log, and closes it, all nice and tidy. For example, you could do:

Code:

int a = 20;
Log("flarp.txt", "%d", a);

and "20" would end up in flarp.txt. Trouble is, I can't figure out how to take the variable number of args passed to the Log function and then pass those arguments from Log to printf. I tried the following, expecting that it wouldn't work:

Code:

#include <stdio.h>
#include <stdarg.h>

void printme(char * str, ...) {
    va_list arglist;
    va_start(arglist, str);
    printf(str, arglist);
    va_end(arglist);
};

int main () {
    int a = 20;
    printme("%d",a);
    getchar();
    return 0;
};

And the result was some random number, which I suspect was the address of the first argument in the "..." in "printme()". (EDIT: it is the value of "arglist", which I expect is a pointer). So, help, please?