wprintf and %s for substrings

[jovial crescent]

How do I print a substring with fixed length?

const wchar_t(&arrRef)[5] = L"ABCD";
    
    wprintf(L"%1s\n", arrRef);

this prints ABCD, the array takes 5 wide chars, each 2 bytes

[fallow onyx]

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[real quiver]

;compile c++

[grizzled saffron]

Program Output

A

cax100#0016 | 60ms | c++ | x86-64 gcc 13.1 | godbolt.org

[jovial crescent]

dafuq

hold on, godbolt doesn't run windows

when I tried this it still prints ABCD

[winged inlet]

You can probably use std::substr

And the first argument should be a wstring

[jovial crescent]

that is a heap allocated copy, I want to skip that

[winged inlet]

Also, wchar_t might not be 2 bytes

its usually 2, but it doesn't have to be

[jovial crescent]

not to mention that if this wstring has \0 in it, wprintf needs to use fixed length to print all the characters

and not %s

[winged inlet]

Yeah, thats true

So yeah, just use std::substr and std::cout 😉

[jovial crescent]

you mean std::wcout

[winged inlet]

Whats the actual issue here?

[jovial crescent]

optimizations

performance diff

[winged inlet]

Yeah, it was a typo

[jovial crescent]

and yes std::wcout<<std::wstring(wchar_ptr, wchar_len)<<L"\n" works just fine

std::wcout.write(arrRef, 1)<<L"\n";

this thing works thank god

it prints

A

maybe I should wipe all of the printf nonsense away from my program (copied from MSDN meant to be used in C) and use wcout

but still this doesn't explain why wprintf is broken

[jovial crescent]

https://stackoverflow.com/questions/17700797/printf-wprintf-s-s-ls-char-and-wchar-errors-not-announced-by-a-compil
yoooooooo what the fuuuuuuuuuuuuuuuu

I am using minGW g++

[spare wren]

I does though sometimes.

[jovial crescent]

bump