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Comment by XJ6w9dTdM

9 hours ago

Yes !

This has been on the back of my mind for a while. And, as other commenters have noted, it would be great for the file to contain the (self-modifiable) Lisp image, a builtin virtual file system, and whatever the application want to use as (runtime modifiable) extra tables.

I find SQLite dynamic linking being basically compatible with ELF dynamic linking to be very impressive, I can imagine that if well done, it cloud replace most uses of AppImages with a much more efficient format, like the author suggests.

How about an option for compressing section contents within the SQLite blobs, since the author mentioned you can't mmap directly the text pages and have to copy anyway ?

There are two extensions that I was thinking would make a SQLite executable truly unique.

First, a linking extension that would allow patching in functions and hooks more directly to allow for a very powerful plug-in system. Imagine the plug-in SQLite defining a BEFORE/AFTER/REPLACE hook for some symbol the host SQLite defines as extensible.

Second, re-linking at runtime. This would require application author cooperation because you won't be able to do that from anywhere, but imagine changing a dependency or loading a plugin at runtime through editing the db, and the interpreter just maps that on demand/automatically in the background, now next time your web server accept(), it calls the new version of the handling function.

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XJ6w9dTdM

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inigyou  8 hours ago

You can do any of this in-memory wife ELF of course, it's just that nobody does and nobody's written the tools for it (the most obscure tool I know of is `ld -r`, which links two or more .o files and produces a new .o file instead of an executable)

  • XJ6w9dTdM  7 hours ago

    For sure, the main advantage is that since the SQLite file format is easy to use compared to ELF, it's more likely that such experiments would be even tried at all.

    I got another one: bundling multiple (completely separate) executables with shared dependencies in the same SQLite, selected by argv[0] when called, like what busybox does