are these lines still needed?

[dmalan]

1. https://github.com/cs50/libcs50/blob/2019/src/cs50.c#L56
2. https://github.com/cs50/libcs50/blob/2019/src/cs50.c#L57
3. https://github.com/cs50/libcs50/blob/2019/src/cs50.c#L77
4. https://github.com/cs50/libcs50/blob/2019/src/cs50.c#L461
5. https://github.com/cs50/libcs50/blob/2019/src/cs50.h#L101

CC @kzidane

[cmlsharp]

Yes on all counts. Each of those lines is necessary to allow the printf-like arguments to get_*.

[dmalan]

@crossroads1112 can you remind me what role https://github.com/cs50/libcs50/blob/2019/src/cs50.h#L101 plays specifically? Is that trick necessary anymore, if we require now that get_string have at least one argument (the prompt) anyway? It's really just the second, third, etc. arguments that are optional now?

[cmlsharp]

That trick was to allow get_string to be called internally by get_int etc. There are two contexts in which get_string can be called: directly, in which it gets its arguments variadic arguments the standard way, or internally by get_int et al in which case their variadic arguments have already been stored in a va_list. This first parameter disambiguates between these two cases. When getstring is called by students, the first parameter is NULL whereas get* pass their own va_list as its first parameter

[dmalan]

Ah, right, thanks!