use unsafe blocks in `sync/`

See merge request redox-os/relibc!505

feat: ignore negative fd and clear its revents in poll(2)

See merge request redox-os/relibc!484

Use unsafe blocks in crypt.h implementation

See merge request redox-os/relibc!503

Use unsafe blocks in assert.h implementation

See merge request redox-os/relibc!502

Use unsafe blocks in arpa/inet.h implementation

See merge request redox-os/relibc!501

Fix the Redox OS test execution command

See merge request redox-os/relibc!500

Test endian.h macros

See merge request !499

Fix little-endian-specific endian.h tests

See merge request !498

Add `endian.h`

See merge request !497

Un-mutexify random() default buffer

See merge request !496

Explain what redox-rt is

See merge request !495

Put random() state behind mutex

See merge request !491

Remove all uses of the legacy scheme syntax

See merge request !492

Fixes for forkpty and dprintf tests

See merge request !494

The former is more portable, even on Linux if for example sudo/doas is used.

Implement ctermid()

See merge request !490

Refactor mktime, timegm and fix wcpncpy test

See merge request !487

swscanf and vswscanf implementation proposal

See merge request redox-os/relibc!472

Implement dprintf and vdprintf

See merge request !489