* remove std.os.spawnThreadAllocator - windows does not support
an explicit stack, so using an allocator for a thread stack
space does not work.
* std.os.spawnThread - instead of accepting a stack argument, the
implementation will directly allocate using OS-specific APIs.
Use std.heap.FixedBufferAllocator combined with
std.heap.DirectAllocator instead.
std.mem.FixedBufferAllocator is moved to std.heap.FixedBufferAllocator
* move std.io.File to std.os.File
* add `zig fmt` to self hosted compiler
* introduce std.io.BufferedAtomicFile API
* introduce std.os.AtomicFile API
* add `std.os.default_file_mode`
* change FileMode on posix from being a usize to a u32
* add std.os.File.mode to return mode of an open file
* std.os.copyFile copies the mode from the source file instead of
using the default file mode for the dest file
* move `std.os.line_sep` to `std.cstr.line_sep`
Before we accepted a nullable allocator for some stuff like
opening files. Now we require an allocator.
Use the mem.FixedBufferAllocator pattern if a bound on the amount
to allocate is known.
This also establishes the pattern that usually an allocator is the
first argument to a function (possibly after "self").
fix docs for std.cstr.addNullByte
self hosted compiler:
* only build docs when explicitly asked to
* clean up main
* stub out zig fmt
Add fallback paths for when the getrandom(2) system call is not
available. Try /dev/urandom first and sysctl(RANDOM_UUID) second.
The sysctl issues a warning in the system logs with some kernels but
that seems like an acceptable tradeoff for the fallback of a fallback.
The purpose of this is:
* Only one way to do things
* Changing a function with void return type to return a possible
error becomes a 1 character change, subtly encouraging
people to use errors.
See #632
Here are some imperfect sed commands for performing this update:
remove arrow:
```
sed -i 's/\(\bfn\b.*\)-> /\1/g' $(find . -name "*.zig")
```
add void:
```
sed -i 's/\(\bfn\b.*\))\s*{/\1) void {/g' $(find ../ -name "*.zig")
```
Some cleanup may be necessary, but this should do the bulk of the work.