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1. Embed this notice
   Paul Cantrell (inthehands@hachyderm.io)'s status on Monday, 10-Mar-2025 05:24:28 JST Paul Cantrell

   • luna, only carbon now

   Print statements in C++ are not threadsafe.

   This language…!

   @luna https://pony.social/@luna/114134087099804076

   • Embed this notice
     Paul Cantrell (inthehands@hachyderm.io)'s status on Monday, 10-Mar-2025 05:40:50 JST Paul Cantrell

     in reply to

     • luna, only carbon now
     • Johan Baltié

     @johan @luna
     I would not describe having a nondeterministic race condition between format specifiers from different threads as being “thread safe,” except in the most uselessly pedantic way imaginable.

     And no, I can’t think of another language that has this problem, because all of them use that magic native internal buffer we refer to as “local expression evaluation.”

   • Embed this notice
     Johan Baltié (johan@pouet.chapril.org)'s status on Monday, 10-Mar-2025 05:40:51 JST Johan Baltié

     in reply to

     • luna, only carbon now

     @inthehands @luna they are thread safe.
     The interleave pb is a different issue
     I am not aware of languages that keep natively internal buffer per thread to avoid interleaving.

     Do you have any example ?

   • Embed this notice
     PaulDavisTheFirst (pauldavisthefirst@fosstodon.org)'s status on Monday, 10-Mar-2025 06:20:24 JST PaulDavisTheFirst

     in reply to

     • luna, only carbon now
     • Johan Baltié

     @johan @inthehands @luna yeah, precisely. The "print statement" in C++ is the same as in C: printf and cousins.

     operator<< is ... an operator and is not inherently more (or less) thread-safe than operator+ or operator=.

     I also agree that is may be considered strange to promote an operator as the default way of printing.

   • Embed this notice
     Paul Cantrell (inthehands@hachyderm.io)'s status on Monday, 10-Mar-2025 06:20:24 JST Paul Cantrell

     in reply to

     • PaulDavisTheFirst
     • luna, only carbon now
     • Johan Baltié

     @PaulDavisTheFirst @johan @luna
     `cout <<` is the generally accepted idiom for printing to stdout in C++, no doubt able that — and yes, promoting that way is strange!

     Technicalities about implementation(“`<<` is just another operator,” “it’s thread-safe at the level of individual stream insertions”, etc) are missing the point. The •standard idiom• is a footgun. That’s the point.

   • Embed this notice
     Johan Baltié (johan@pouet.chapril.org)'s status on Monday, 10-Mar-2025 06:20:25 JST Johan Baltié

     in reply to

     • luna, only carbon now

     @inthehands @luna ok I see where we disagree.
     Stream operators are not equivalent to print statement, each data being fed asap by design.

     And I agree this might be considered as a strange choice to promote this as a default way of printing.

   • Embed this notice
     Paul Cantrell (inthehands@hachyderm.io)'s status on Monday, 10-Mar-2025 07:46:05 JST Paul Cantrell

     in reply to

     • PaulDavisTheFirst
     • luna, only carbon now
     • Johan Baltié

     @johan @PaulDavisTheFirst @luna
     Ha, that’s hilarious! Everything is terrible.

   • Embed this notice
     Johan Baltié (johan@pouet.chapril.org)'s status on Monday, 10-Mar-2025 07:46:06 JST Johan Baltié

     in reply to

     • PaulDavisTheFirst
     • luna, only carbon now

     @inthehands @PaulDavisTheFirst @luna

     Oh, researching other languages choices I discovered that Python as a very strange behavior:

     https://stackoverflow.com/questions/42867866/what-makes-python3s-print-function-thread-safe#64283201

   • Embed this notice
     Michael Kohne (mhkohne@mastodon.social)'s status on Monday, 10-Mar-2025 09:22:33 JST Michael Kohne

     in reply to

     • luna, only carbon now

     @inthehands @luna I think it might be better if it just threw a fucking pointer and crashed rather than do this shit.

   • Embed this notice
     Paul Cantrell (inthehands@hachyderm.io)'s status on Monday, 10-Mar-2025 09:22:33 JST Paul Cantrell

     in reply to

     • Michael Kohne
     • luna, only carbon now

     @mhkohne @luna
     Why not both!