Imports

<h1><a id="imports"></a>World imports</h1> <ul> <li>Imports: <ul> <li>interface <a href="#wasi_io_poll_0_2_11"><code>wasi:io/[email protected]</code></a></li> <li>interface <a href="#wasi_clocks_monotonic_clock_0_2_11"><code>wasi:clocks/[email protected]</code></a></li> <li>interface <a href="#wasi_clocks_wall_clock_0_2_11"><code>wasi:clocks/[email protected]</code></a></li> <li>interface <a href="#wasi_clocks_timezone_0_2_11"><code>wasi:clocks/[email protected]</code></a></li> </ul> </li> </ul> <h2><a id="wasi_io_poll_0_2_11"></a>Import interface wasi:io/[email protected]</h2> <p>A poll API intended to let users wait for I/O events on multiple handles at once.</p> <hr /> <h3>Types</h3> <h4><a id="pollable"></a><code>resource pollable</code></h4> <h2><a href="#pollable"><code>pollable</code></a> represents a single I/O event which may be ready, or not.</h2> <h3>Functions</h3> <h4><a id="method_pollable_ready"></a><code>[method]pollable.ready: func</code></h4> <p>Return the readiness of a pollable. This function never blocks.</p> <p>Returns <code>true</code> when the pollable is ready, and <code>false</code> otherwise.</p> <h5>Params</h5> <ul> <li><a id="method_pollable_ready.self"></a><code>self</code>: borrow&lt;<a href="#pollable"><a href="#pollable"><code>pollable</code></a></a>&gt;</li> </ul> <h5>Return values</h5> <ul> <li><a id="method_pollable_ready.0"></a> <code>bool</code></li> </ul> <h4><a id="method_pollable_block"></a><code>[method]pollable.block: func</code></h4> <p><code>block</code> returns immediately if the pollable is ready, and otherwise blocks until ready.</p> <p>This function is equivalent to calling <code>poll.poll</code> on a list containing only this pollable.</p> <h5>Params</h5> <ul> <li><a id="method_pollable_block.self"></a><code>self</code>: borrow&lt;<a href="#pollable"><a href="#pollable"><code>pollable</code></a></a>&gt;</li> </ul> <h4><a id="poll"></a><code>poll: func</code></h4> <p>Poll for completion on a set of pollables.</p> <p>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.</p> <p>The result <code>list&lt;u32&gt;</code> contains one or more indices of handles in the argument list that is ready for I/O.</p> <p>This function traps if either:</p> <ul> <li>the list is empty, or:</li> <li>the list contains more elements than can be indexed with a <code>u32</code> value.</li> </ul> <p>A timeout can be implemented by adding a pollable from the wasi-clocks API to the list.</p> <p>This function does not return a <code>result</code>; polling in itself does not do any I/O so it doesn't fail. If any of the I/O sources identified by the pollables has an error, it is indicated by marking the source as being ready for I/O.</p> <h5>Params</h5> <ul> <li><a id="poll.in"></a><code>in</code>: list&lt;borrow&lt;<a href="#pollable"><a href="#pollable"><code>pollable</code></a></a>&gt;&gt;</li> </ul> <h5>Return values</h5> <ul> <li><a id="poll.0"></a> list&lt;<code>u32</code>&gt;</li> </ul> <h2><a id="wasi_clocks_monotonic_clock_0_2_11"></a>Import interface wasi:clocks/[email protected]</h2> <p>WASI Monotonic Clock is a clock API intended to let users measure elapsed time.</p> <p>It is intended to be portable at least between Unix-family platforms and Windows.</p> <p>A monotonic clock is a clock which has an unspecified initial value, and successive reads of the clock will produce non-decreasing values.</p> <hr /> <h3>Types</h3> <h4><a id="pollable"></a><code>type pollable</code></h4> <p><a href="#pollable"><a href="#pollable"><code>pollable</code></a></a></p> <p> <h4><a id="instant"></a><code>type instant</code></h4> <p><code>u64</code></p> <p>An instant in time, in nanoseconds. An instant is relative to an unspecified initial value, and can only be compared to instances from the same monotonic-clock. <h4><a id="duration"></a><code>type duration</code></h4> <p><code>u64</code></p> <p>A duration of time, in nanoseconds. <hr /> <h3>Functions</h3> <h4><a id="now"></a><code>now: func</code></h4> <p>Read the current value of the clock.</p> <p>The clock is monotonic, therefore calling this function repeatedly will produce a sequence of non-decreasing values.</p> <p>For completeness, this function traps if it's not possible to represent the value of the clock in an <a href="#instant"><code>instant</code></a>. Consequently, implementations should ensure that the starting time is low enough to avoid the possibility of overflow in practice.</p> <h5>Return values</h5> <ul> <li><a id="now.0"></a> <a href="#instant"><a href="#instant"><code>instant</code></a></a></li> </ul> <h4><a id="resolution"></a><code>resolution: func</code></h4> <p>Query the resolution of the clock. Returns the duration of time corresponding to a clock tick.</p> <h5>Return values</h5> <ul> <li><a id="resolution.0"></a> <a href="#duration"><a href="#duration"><code>duration</code></a></a></li> </ul> <h4><a id="subscribe_instant"></a><code>subscribe-instant: func</code></h4> <p>Create a <a href="#pollable"><code>pollable</code></a> which will resolve once the specified instant has occurred.</p> <h5>Params</h5> <ul> <li><a id="subscribe_instant.when"></a><code>when</code>: <a href="#instant"><a href="#instant"><code>instant</code></a></a></li> </ul> <h5>Return values</h5> <ul> <li><a id="subscribe_instant.0"></a> own&lt;<a href="#pollable"><a href="#pollable"><code>pollable</code></a></a>&gt;</li> </ul> <h4><a id="subscribe_duration"></a><code>subscribe-duration: func</code></h4> <p>Create a <a href="#pollable"><code>pollable</code></a> that will resolve after the specified duration has elapsed from the time this function is invoked.</p> <h5>Params</h5> <ul> <li><a id="subscribe_duration.when"></a><code>when</code>: <a href="#duration"><a href="#duration"><code>duration</code></a></a></li> </ul> <h5>Return values</h5> <ul> <li><a id="subscribe_duration.0"></a> own&lt;<a href="#pollable"><a href="#pollable"><code>pollable</code></a></a>&gt;</li> </ul> <h2><a id="wasi_clocks_wall_clock_0_2_11"></a>Import interface wasi:clocks/[email protected]</h2> <p>WASI Wall Clock is a clock API intended to let users query the current time. The name &quot;wall&quot; makes an analogy to a &quot;clock on the wall&quot;, which is not necessarily monotonic as it may be reset.</p> <p>It is intended to be portable at least between Unix-family platforms and Windows.</p> <p>A wall clock is a clock which measures the date and time according to some external reference.</p> <p>External references may be reset, so this clock is not necessarily monotonic, making it unsuitable for measuring elapsed time.</p> <p>It is intended for reporting the current date and time for humans.</p> <hr /> <h3>Types</h3> <h4><a id="datetime"></a><code>record datetime</code></h4> <p>A time and date in seconds plus nanoseconds.</p> <h5>Record Fields</h5> <ul> <li><a id="datetime.seconds"></a><code>seconds</code>: <code>u64</code></li> <li><a id="datetime.nanoseconds"></a><code>nanoseconds</code>: <code>u32</code></li> </ul> <hr /> <h3>Functions</h3> <h4><a id="now"></a><code>now: func</code></h4> <p>Read the current value of the clock.</p> <p>This clock is not monotonic, therefore calling this function repeatedly will not necessarily produce a sequence of non-decreasing values.</p> <p>The returned timestamps represent the number of seconds since 1970-01-01T00:00:00Z, also known as <a href="https://pubs.opengroup.org/onlinepubs/9699919799/xrat/V4_xbd_chap04.html#tag_21_04_16">POSIX's Seconds Since the Epoch</a>, also known as <a href="https://en.wikipedia.org/wiki/Unix_time">Unix Time</a>.</p> <p>The nanoseconds field of the output is always less than 1000000000.</p> <h5>Return values</h5> <ul> <li><a id="now.0"></a> <a href="#datetime"><a href="#datetime"><code>datetime</code></a></a></li> </ul> <h4><a id="resolution"></a><code>resolution: func</code></h4> <p>Query the resolution of the clock.</p> <p>The nanoseconds field of the output is always less than 1000000000.</p> <h5>Return values</h5> <ul> <li><a id="resolution.0"></a> <a href="#datetime"><a href="#datetime"><code>datetime</code></a></a></li> </ul> <h2><a id="wasi_clocks_timezone_0_2_11"></a>Import interface wasi:clocks/[email protected]</h2> <hr /> <h3>Types</h3> <h4><a id="datetime"></a><code>type datetime</code></h4> <p><a href="#datetime"><a href="#datetime"><code>datetime</code></a></a></p> <p> <h4><a id="timezone_display"></a><code>record timezone-display</code></h4> <p>Information useful for displaying the timezone of a specific <a href="#datetime"><code>datetime</code></a>.</p> <p>This information may vary within a single <code>timezone</code> to reflect daylight saving time adjustments.</p> <h5>Record Fields</h5> <ul> <li> <p><a id="timezone_display.utc_offset"></a><a href="#utc_offset"><code>utc-offset</code></a>: <code>s32</code></p> <p>The number of seconds difference between UTC time and the local time of the timezone. <p>The returned value will always be less than 86400 which is the number of seconds in a day (24<em>60</em>60).</p> <p>In implementations that do not expose an actual time zone, this should return 0.</p> </li> <li> <p><a id="timezone_display.name"></a><code>name</code>: <code>string</code></p> <p>The abbreviated name of the timezone to display to a user. The name `UTC` indicates Coordinated Universal Time. Otherwise, this should reference local standards for the name of the time zone. <p>In implementations that do not expose an actual time zone, this should be the string <code>UTC</code>.</p> <p>In time zones that do not have an applicable name, a formatted representation of the UTC offset may be returned, such as <code>-04:00</code>.</p> </li> <li> <p><a id="timezone_display.in_daylight_saving_time"></a><code>in-daylight-saving-time</code>: <code>bool</code></p> <p>Whether daylight saving time is active. <p>In implementations that do not expose an actual time zone, this should return false.</p> </li> </ul> <hr /> <h3>Functions</h3> <h4><a id="display"></a><code>display: func</code></h4> <p>Return information needed to display the given <a href="#datetime"><code>datetime</code></a>. This includes the UTC offset, the time zone name, and a flag indicating whether daylight saving time is active.</p> <p>If the timezone cannot be determined for the given <a href="#datetime"><code>datetime</code></a>, return a <a href="#timezone_display"><code>timezone-display</code></a> for <code>UTC</code> with a <a href="#utc_offset"><code>utc-offset</code></a> of 0 and no daylight saving time.</p> <h5>Params</h5> <ul> <li><a id="display.when"></a><code>when</code>: <a href="#datetime"><a href="#datetime"><code>datetime</code></a></a></li> </ul> <h5>Return values</h5> <ul> <li><a id="display.0"></a> <a href="#timezone_display"><a href="#timezone_display"><code>timezone-display</code></a></a></li> </ul> <h4><a id="utc_offset"></a><code>utc-offset: func</code></h4> <p>The same as <a href="#display"><code>display</code></a>, but only return the UTC offset.</p> <h5>Params</h5> <ul> <li><a id="utc_offset.when"></a><code>when</code>: <a href="#datetime"><a href="#datetime"><code>datetime</code></a></a></li> </ul> <h5>Return values</h5> <ul> <li><a id="utc_offset.0"></a> <code>s32</code></li> </ul>