DragonFly At DragonFly 1.0-CURRENT

CoolVibe writes "For months, the DragonflyBSD fork of FreeBSD was maintaining compatibility with the existing FreeBSD-STABLE branch by using the 'FreeBSD 4.8-STABLE' name internally. In a few commits, Matt Dillon changed all the names, and DragonFly is finally sailing under its own banner. Things that DragonFlyBSD already has that FreeBSD-STABLE doesn't are, among others, application checkpointing, variant symlinks (not unlike Domain OS), Light-weight kernel threads, a more efficient slab-allocator, a multithreaded network stack, and the rcNG system."

Comments

Variant symlinks are really cool

[Euphonious Coward]

Variant symlinks as found in Domain OS (nee Domainix, nee Apollo Aegis) are symlinks that refer to environment variables, e.g.

ln -s '/etc-$(HOSTNAME)' /etc

to help enable sharing the root file system. (I don't know the variable-reference syntax used in Dragonfly). This was one of the really cool things about Aegis, which was based on Multics, not Unix. Unix/Linux/BSD have still not caught up to the networking capabilities of Aegis, and what they do have is usually clunkier than the way it was done in Aegis.

I thought about implementing variant symlinks on Linux. Probably it would need a new system call to tell the kernel where the process keeps its environment variables, to be run at each program startup, and a new process table entry field.