Thanks! Looks like it is a glibc (and musl) feature, though this led me to discover funopen() in BSD and macOS: https://man.openbsd.org/funopen.3 https://man.op

Thanks! Looks like it is a glibc (and musl) feature, though this led me to discover funopen() in BSD and macOS: https://man.openbsd.org/funopen.3 https://man.openbsd.org/funopen.3