It has been for decades at this point. thiago's blog posts which introduced me to the topic over a decade ago (and is still one of the best explainers) points o

It has been for decades at this point. thiago's blog posts which introduced me to the topic over a decade ago (and is still one of the best explainers) points out that posix_spawn was introduced in POSIX.1-2001: https://web.archive.org/web/20120718152158/http://www.macieira.org/blog/2012/07/forkfd-part-1-launching-processes-on-unix/ https://web.archive.org/web/20120718152158/http://www.maciei...