db33973e0a
This is done without using Microsoft's internal APIs. MAP_PRIVATE mappings are copied to the subprocess via a pipe, since Microsoft doesn't want us to have proper COW pages. MAP_SHARED mappings are remapped without needing to do any copying. Global variables need copying along with the stack and the whole heap of anonymous mem. This actually improves the reliability of the redbean http server although one shouldn't expect 10k+ connections on a home computer that isn't running software built to serve like Linux or FreeBSD. |
||
|---|---|---|
| .. | ||
| calls | ||
| consts | ||
| errfuns | ||
| machcalls | ||
| stubs | ||
| README.md | ||
| consensus.py | ||
| consts.sh | ||
| errfuns.h | ||
| errfuns.sh | ||
| g_syscount.S | ||
| gen.sh | ||
| machcalls.sh | ||
| macros.h | ||
| restorert.S | ||
| syscall.S | ||
| syscalls.sh | ||
| systemfive.S | ||
| sysv.mk | ||
| versions.txt | ||
README.md
SYNOPSIS
System Five Import Libraries
OVERVIEW
Bell System Five is the umbrella term we use to describe Linux, FreeBSD, OpenBSD, and Mac OS X which all have nearly-identical application binary interfaces that stood the test of time, having definitions nearly the same as those of AT&T back in the 1980's.
Cosmopolitan aims to help you build apps that can endure over the course of decades, just like these systems have: without needing to lift a finger for maintenance churn, broken builds, broken hearts.
The challenge to System V binary compatibility basically boils down to numbers. All these systems agree on what services are provided, but tend to grant them wildly different numbers.
We address this by putting all the numbers in a couple big shell scripts, ask the GNU Assembler to encode them into binaries using an efficient LEB128 encoding, unpacked by _init(), and ref'd via extern const. It gives us good debuggability, and any costs are gained back by fewer branches in wrapper functions.z