wasi:io/error@0.2.1wasi:io/poll@0.2.1wasi:io/streams@0.2.1wasi:io/error@0.2.2wasi:io/poll@0.2.2wasi:io/streams@0.2.2resource errorresource errorA resource which represents some error information.
The only method provided by this resource is to-debug-string,
which provides some human-readable information about the error.
option<wasi:filesystem/types/error-code>The set of functions which can "downcast" an error into a more
concrete type is open.
Functions
-[method]error.to-debug-string: func
+[method]error.to-debug-string: func
Returns a string that is suitable to assist humans in debugging
this error.
WARNING: The returned string should not be consumed mechanically!
@@ -35,41 +35,41 @@ details. Parsing this string is a major platform-compatibility
hazard.
Params
Return values
-Import interface wasi:io/poll@0.2.1
+Import interface wasi:io/poll@0.2.2
A poll API intended to let users wait for I/O events on multiple handles
at once.
Types
-resource pollable
+resource pollable
pollable represents a single I/O event which may be ready, or not.
Functions
-[method]pollable.ready: func
+[method]pollable.ready: func
Return the readiness of a pollable. This function never blocks.
Returns true when the pollable is ready, and false otherwise.
Params
Return values
-[method]pollable.block: func
+[method]pollable.block: func
block returns immediately if the pollable is ready, and otherwise
blocks until ready.
This function is equivalent to calling poll.poll on a list
containing only this pollable.
Params
-poll: func
+poll: func
Poll for completion on a set of pollables.
This function takes a list of pollables, which identify I/O sources of
interest, and waits until one or more of the events is ready for I/O.
@@ -88,44 +88,44 @@ the pollables has an error, it is indicated by marking the source as
being ready for I/O.
Params
Return values
-Import interface wasi:io/streams@0.2.1
+Import interface wasi:io/streams@0.2.2
WASI I/O is an I/O abstraction API which is currently focused on providing
stream types.
In the future, the component model is expected to add built-in stream types;
when it does, they are expected to subsume this API.
Types
-type error
+type error
-#### `type pollable`
+#### `type pollable`
[`pollable`](#pollable)
-#### `variant stream-error`
+#### `variant stream-error`
An error for input-stream and output-stream operations.
Variant Cases
-
-
last-operation-failed: own<error>
+last-operation-failed: own<error>
The last operation (a write or flush) failed before completion.
More information is available in the error payload.
After this, the stream will be closed. All future operations return
stream-error::closed.
-
-
+
The stream is closed: no more input will be accepted by the
stream. A closed output-stream will return this error on all
future operations.
-resource input-stream
+resource input-stream
An input bytestream.
input-streams are non-blocking to the extent practical on underlying
platforms. I/O operations always return promptly; if fewer bytes are
@@ -133,7 +133,7 @@ promptly available than requested, they return the number of bytes promptly
available, which could even be zero. To wait for data to be available,
use the subscribe function to obtain a pollable which can be polled
for using wasi:io/poll.
-resource output-stream
+resource output-stream
An output bytestream.
output-streams are non-blocking to the extent practical on
underlying platforms. Except where specified otherwise, I/O operations also
@@ -145,7 +145,7 @@ polled for using wasi:io/poll.
progress may result in the data being lost. Before dropping the stream,
be sure to fully flush your writes.
Functions
-[method]input-stream.read: func
+[method]input-stream.read: func
Perform a non-blocking read from the stream.
When the source of a read is binary data, the bytes from the source
are returned verbatim. When the source of a read is known to the
@@ -169,51 +169,51 @@ as a return value by the callee. The callee may return a list of bytes
less than len in size while more bytes are available for reading.
Params
-self: borrow<input-stream>len: u64self: borrow<input-stream>len: u64
Return values
-- result<list<
u8>, stream-error>
+- result<list<
u8>, stream-error>
-[method]input-stream.blocking-read: func
+[method]input-stream.blocking-read: func
Read bytes from a stream, after blocking until at least one byte can
be read. Except for blocking, behavior is identical to read.
Params
-self: borrow<input-stream>len: u64self: borrow<input-stream>len: u64
Return values
-- result<list<
u8>, stream-error>
+- result<list<
u8>, stream-error>
-[method]input-stream.skip: func
+[method]input-stream.skip: func
Skip bytes from a stream. Returns number of bytes skipped.
Behaves identical to read, except instead of returning a list
of bytes, returns the number of bytes consumed from the stream.
Params
-self: borrow<input-stream>len: u64self: borrow<input-stream>len: u64
Return values
-- result<
u64, stream-error>
+- result<
u64, stream-error>
-[method]input-stream.blocking-skip: func
+[method]input-stream.blocking-skip: func
Skip bytes from a stream, after blocking until at least one byte
can be skipped. Except for blocking behavior, identical to skip.
Params
-self: borrow<input-stream>len: u64self: borrow<input-stream>len: u64
Return values
-- result<
u64, stream-error>
+- result<
u64, stream-error>
-[method]input-stream.subscribe: func
+[method]input-stream.subscribe: func
Create a pollable which will resolve once either the specified stream
has bytes available to read or the other end of the stream has been
closed.
@@ -222,13 +222,13 @@ Implementations may trap if the input-streampollables created with this function are dropped.
Params
-self: borrow<input-stream>self: borrow<input-stream>
Return values
-[method]output-stream.check-write: func
+[method]output-stream.check-write: func
Check readiness for writing. This function never blocks.
Returns the number of bytes permitted for the next call to write,
or an error. Calling write with more bytes than this function has
@@ -238,13 +238,13 @@ become ready when this function will report at least 1 byte, or an
error.
Params
-self: borrow<output-stream>self: borrow<output-stream>
Return values
-- result<
u64, stream-error>
+- result<
u64, stream-error>
-[method]output-stream.write: func
+[method]output-stream.write: func
Perform a write. This function never blocks.
When the destination of a write is binary data, the bytes from
contents are written verbatim. When the destination of a write is
@@ -257,14 +257,14 @@ length of less than or equal to n. Otherwise, this function will trap.
the last call to check-write provided a permit.
Params
-self: borrow<output-stream>contents: list<u8>self: borrow<output-stream>contents: list<u8>
Return values
-- result<_,
stream-error>
+- result<_,
stream-error>
-[method]output-stream.blocking-write-and-flush: func
+[method]output-stream.blocking-write-and-flush: func
Perform a write of up to 4096 bytes, and then flush the stream. Block
until all of these operations are complete, or an error occurs.
This is a convenience wrapper around the use of check-write,
@@ -288,14 +288,14 @@ let _ = this.check-write(); // eliding error handling
self: borrow<output-stream>contents: list<u8>self: borrow<output-stream>contents: list<u8>stream-error>stream-error>[method]output-stream.flush: func[method]output-stream.flush: funcRequest to flush buffered output. This function never blocks.
This tells the output-stream that the caller intends any buffered
output to be flushed. the output which is expected to be flushed
@@ -306,24 +306,24 @@ completed. The subscribe pollable will become ready when the
flush has completed and the stream can accept more writes.
self: borrow<output-stream>self: borrow<output-stream>stream-error>stream-error>[method]output-stream.blocking-flush: func[method]output-stream.blocking-flush: funcRequest to flush buffered output, and block until flush completes and stream is ready for writing again.
self: borrow<output-stream>self: borrow<output-stream>stream-error>stream-error>[method]output-stream.subscribe: func[method]output-stream.subscribe: funcCreate a pollable which will resolve once the output-stream
is ready for more writing, or an error has occurred. When this
pollable is ready, check-write will return ok(n) with n>0, or an
@@ -334,13 +334,13 @@ Implementations may trap if the output-streams created with this function are dropped.pollable
self: borrow<output-stream>self: borrow<output-stream>[method]output-stream.write-zeroes: func[method]output-stream.write-zeroes: funcWrite zeroes to a stream.
This should be used precisely like write with the exact same
preconditions (must use check-write first), but instead of
@@ -348,14 +348,14 @@ passing a list of bytes, you simply pass the number of zero-bytes
that should be written.
self: borrow<output-stream>len: u64self: borrow<output-stream>len: u64stream-error>stream-error>[method]output-stream.blocking-write-zeroes-and-flush: func[method]output-stream.blocking-write-zeroes-and-flush: funcPerform a write of up to 4096 zeroes, and then flush the stream. Block until all of these operations are complete, or an error occurs.
@@ -379,14 +379,14 @@ let _ = this.check-write(); // eliding error handlingself: borrow<output-stream>len: u64self: borrow<output-stream>len: u64stream-error>stream-error>[method]output-stream.splice: func[method]output-stream.splice: funcRead from one stream and write to another.
The behavior of splice is equivalent to:
len.
self: borrow<output-stream>src: borrow<input-stream>len: u64self: borrow<output-stream>src: borrow<input-stream>len: u64u64, stream-error>u64, stream-error>[method]output-stream.blocking-splice: func[method]output-stream.blocking-splice: funcRead from one stream and write to another, with blocking.
This is similar to splice, except that it blocks until the
output-stream is ready for writing, and the input-stream
is ready for reading, before performing the splice.
self: borrow<output-stream>src: borrow<input-stream>len: u64self: borrow<output-stream>src: borrow<input-stream>len: u64u64, stream-error>u64, stream-error>