how to wrap c scanf procedure in nim

[PMunch]

You will have to be more specific. What isn't working, what have you tried, 
etc.? It should be the same signature as a printf, so something like this 
should work:
    
    
    proc scanf(formatstr: cstring) {.importc: "scanf", varargs, header: 
"<stdio.h>".}
    
    
    Run