cosmopolitan/libc/sysv
Justine Tunney 1d4eb08fa1
Support non-blocking i/o across platforms
This change introduces new tests for `O_NONBLOCK` and `SOCK_NONBLOCK` to
confirm that non-blocking i/o is now working on all supported platforms,
including Windows. For example, you can now say on Windows, MacOS, etc.:

    socket(AF_INET, SOCK_STREAM | SOCK_NONBLOCK, IPPROTO_TCP);

To create a non-blocking IPv4 TCP socket. Or you can enable non-blocking
i/o on an existing socket / pipe / etc. file descriptor by calling fcntl

    fcntl(fd, F_SETFL, fcntl(fd, F_GETFL) | O_NONBLOCK);

This functionality is polyfilled on older Linux kernels too, e.g. RHEL5.
Now that fcntl() support is much better the FIOCLEX / FIONCLEX polyfills
for ioctl() have been removed since they're ugly non-POSIX diameond APIs

This change fixes a weakness in kprintf() that was causing Windows trace
tools to frequently crash.
2023-07-23 02:56:47 -07:00
..
calls Fully support OpenBSD 7.3 2023-07-01 18:14:27 -07:00
consts Support non-blocking i/o across platforms 2023-07-23 02:56:47 -07:00
dos2errno Introduce native support for MacOS ARM64 2023-05-20 04:17:03 -07:00
errfuns Get --ftrace working on aarch64 2023-06-05 23:35:31 -07:00
consts.sh Support non-blocking i/o across platforms 2023-07-23 02:56:47 -07:00
describeos.greg.c Remove malloc() dependency on pledge() / unveil() 2022-07-24 21:51:37 -07:00
dos2errno.sh Support non-blocking i/o across platforms 2023-07-23 02:56:47 -07:00
errfun.S Introduce native support for MacOS ARM64 2023-05-20 04:17:03 -07:00
errfun2.c Fix bugs in cosmocc toolchain 2023-06-08 23:44:03 -07:00
errfuns.h Get aarch64 hello world working 2023-05-10 04:20:47 -07:00
errfuns.sh Change license 2020-12-27 17:18:44 -08:00
errno.c Make considerably more progress on AARCH64 2023-05-12 22:42:57 -07:00
errno_location.greg.c Make improvements 2023-07-10 04:35:14 -07:00
gen.sh Get --ftrace working on aarch64 2023-06-05 23:35:31 -07:00
hostos.S Introduce native support for MacOS ARM64 2023-05-20 04:17:03 -07:00
macros.internal.h Fully support OpenBSD 7.3 2023-07-01 18:14:27 -07:00
README.md Initial import 2020-06-15 07:18:57 -07:00
restorert.S Get LIBC_RUNTIME and LIBC_CALLS building on aarch64 2023-05-10 04:20:47 -07:00
strace.greg.c Make more threading improvements 2022-11-01 23:28:26 -07:00
syscall.S Get --ftrace working on aarch64 2023-06-05 23:35:31 -07:00
syscalls.sh Fully support OpenBSD 7.3 2023-07-01 18:14:27 -07:00
syscon.S Improve aarch64 native support some more 2023-06-04 08:58:47 -07:00
syscount.S Make considerably more progress on AARCH64 2023-05-12 22:42:57 -07:00
syslib.S Introduce native support for MacOS ARM64 2023-05-20 04:17:03 -07:00
sysret.c Get LIBC_RUNTIME and LIBC_CALLS building on aarch64 2023-05-10 04:20:47 -07:00
systemfive.S Make improvements 2023-07-10 04:35:14 -07:00
sysv.mk Get --ftrace working on aarch64 2023-06-05 23:35:31 -07:00

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