Question

I’m getting this warning from sccanf():

../../../../ext/oedipus/oedipus.c:211: warning: conversion lacks type at end of format

Which comes from this line:

sscanf(v, "%h", &s);

Here s is a short.

I know I can ignore the warning, but up to this point I was warning free, so I’d like to silence it if possible. What is sscanf() expecting differently?

Answer 1

You need to use %hd for a short. %h isn’t valid by itself. From the man page:

h

Indicates that the conversion will be one of d, i, o, u, x, X, or n and the next pointer is a pointer to a short int or unsigned short int (rather than int).

Please don’t ignore warnings – they usually mean something has gone wrong. This case is a good example – your compiler appeared to do the “right thing”, but relying on undefined behaviour is always a bad idea.