* All the data types from `@import("builtin")` are moved to
`@import("std").builtin`. The target-related types are moved
to `std.Target`. This allows the data types to have methods, such as
`std.Target.current.isDarwin()`.
* `std.os.windows.subsystem` is moved to
`std.Target.current.subsystem`.
* Remove the concept of the panic package from the compiler
implementation. Instead, `std.builtin.panic` is always the panic
function. It checks for `@hasDecl(@import("root"), "panic")`,
or else provides a default implementation.
This is an important step for multibuilds (#3028). Without this change,
the types inside the builtin namespace look like different types, when
trying to merge builds with different target settings. With this change,
Zig can figure out that, e.g., `std.builtin.Os` (the enum type) from one
compilation and `std.builtin.Os` from another compilation are the same
type, even if the target OS value differs.
The sockaddr pointer and size of the accept function points to a data structure that can only be determined at runtime. The only requirement is that it must be large enough to hold 2 bytes for the address family value. Typeical usage of the socket API is for UDP/TCP IPv4 and IPv6 sockets, which use sockaddr_in and sockaddr_in6. And some sockets can actually support both simultaneously in which case the app may want to have access to the size of the returned sockaddr. Operating systems can even support custom protocols where they use custom sockaddr data structures. In this case the standard library would have no knowledge of the actual size of the sockaddr being passed into the accept function. In this case the standard library should defer to the app to pass in the size of their structure.
* Added `std.c.unlinkat` and `std.os.unlinkat`.
* Removed `std.fs.MAX_BUF_BYTES` (this declaration never made it to
master branch)
* Added `std.fs.Dir.deleteTree` to be used on an open directory handle.
* `std.fs.deleteTree` has better behavior for both relative and
absolute paths. For absolute paths, it opens the base directory
and uses that handle for subsequent operations. For relative paths,
it does a similar strategy, using the cwd handle.
* The error set of `std.fs.deleteTree` is improved to no longer have
these possible errors:
- OutOfMemory
- FileTooBig
- IsDir
- DirNotEmpty
- PathAlreadyExists
- NoSpaceLeft
* Added `std.fs.Dir.posix_cwd` which is a statically initialized
directory representing the current working directory.
* The error set of `std.Dir.open` is improved to no longer have these
possible errors:
- FileTooBig
- IsDir
- NoSpaceLeft
- PathAlreadyExists
- OutOfMemory
* Added more alternative functions to `std.fs` for when the path
parameter is a null terminated string. This can sometimes be more
effecient on systems which have an ABI based on null terminated
strings.
* Added `std.fs.Dir.openDir`, `std.fs.Dir.deleteFile`, and
`std.fs.Dir.deleteDir` which all operate on an open directory handle.
* `std.fs.Walker.Entry` now has a `dir` field, which can be used to do
operations directly on `std.fs.Walker.Entry.basename`, avoiding
`error.NameTooLong` for deeply nested paths.
* Added more docs to `std.os.OpenError`
This commit does the POSIX components for these changes. I plan to
follow up shortly with a commit for Windows.
* `std.os.execve` had the wrong name; it should have been
`std.os.execvpe`. This is now corrected.
* introduce `std.os.execveC` which does not look at PATH, and uses
null terminated parameters, matching POSIX ABIs. It does not
require an allocator.
* fix typo nonsense doc comment in `std.fs.MAX_PATH_BYTES`.
* introduce `std.os.execvpeC`, which is like `execvpe` except it
uses null terminated parameters, matching POSIX ABIs, and thus
does not require an allocator.
* `std.os.execvpe` implementation is reworked to only convert
parameters and then delegate to `std.os.execvpeC`.
* `std.os.execvpeC` improved to handle `ENOTDIR`. See #3415
