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   luna, only carbon now (luna@pony.social)'s status on Monday, 10-Mar-2025 21:24:35 JST luna, only carbon now

   questions that can really derail a sunday evening:

   is std::cout thread-safe?

   (not in the way you'd want it to be, no)

   • Haelwenn /элвэн/ :triskell: and Doughnut Lollipop 【記録係】:blobfoxgooglymlem: like this.
   • Rich Felker, Haelwenn /элвэн/ :triskell: and Doughnut Lollipop 【記録係】:blobfoxgooglymlem: repeated this.
   • Embed this notice
     luna, only carbon now (luna@pony.social)'s status on Monday, 10-Mar-2025 21:24:37 JST luna, only carbon now

     in reply to

     Consider this code. One thread repeatedly prints the number 100 in decimal to std::cout. Another thread repeatedly prints the number 0x100 in hex (which will output as '100') to std::cout.

     You might reasonably expect that the output will simply be '100' over and over and over.

     Unfortunately, the calls to operator<< can get interleaved so you end up with crosstalk of the format specifiers:

     Doughnut Lollipop 【記録係】:blobfoxgooglymlem: likes this.
   • Embed this notice
     Rich Felker (dalias@hachyderm.io)'s status on Monday, 10-Mar-2025 21:25:48 JST Rich Felker

     in reply to

     @luna The whole modal formatting thing is gratuitously stupid. It's slower, uglier, and had awful gotchas like this compared to printf.

   • Embed this notice
     Steve Canon (steve@discuss.systems)'s status on Monday, 10-Mar-2025 22:53:06 JST Steve Canon

     in reply to

     • Josh Simmons

     @dotstdy @luna iostream formatting is the most clown-shoes misfeature in the whole clown-shoes language.

   • Embed this notice
     Josh Simmons (dotstdy@mastodon.social)'s status on Monday, 10-Mar-2025 22:53:07 JST Josh Simmons

     in reply to

     @luna tfw you're not even better than printf on any axis

     Rich Felker repeated this.
   • Embed this notice
     Graham Sutherland / Polynomial (gsuberland@chaos.social)'s status on Tuesday, 11-Mar-2025 02:24:01 JST Graham Sutherland / Polynomial

     in reply to

     @luna it's thr safead

     Doughnut Lollipop 【記録係】:blobfoxgooglymlem: likes this.