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<link title="Weak_hashtbl" rel="Chapter" href="Weak_hashtbl.html"><title>File_tail</title>
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<h1>Module <a href="type_File_tail.html">File_tail</a></h1>
<pre><span class="keyword">module</span> File_tail: <code class="code">sig</code> <a href="File_tail.html">..</a> <code class="code">end</code></pre><div class="info module top">
<code class="code">File_replaced</code> occurs if the inode of the file changed and the file tail was
configured with <code class="code">ignore_inode_change = false</code>.<br>
</div>
<hr width="100%">
<pre><span class="keyword">module</span> <a href="File_tail.Error.html">Error</a>: <code class="code">sig</code> <a href="File_tail.Error.html">..</a> <code class="code">end</code></pre>
<pre><span class="keyword">module</span> <a href="File_tail.Warning.html">Warning</a>: <code class="code">sig</code> <a href="File_tail.Warning.html">..</a> <code class="code">end</code></pre>
<pre><span class="keyword">module</span> <a href="File_tail.Update.html">Update</a>: <code class="code">sig</code> <a href="File_tail.Update.html">..</a> <code class="code">end</code></pre>
<pre><span id="VALcreate"><span class="keyword">val</span> create</span> : <code class="type">?read_buf_len:int -><br> ?read_delay:Core.Std.Time.Span.t -><br> ?retry_null_reads:bool -><br> ?break_on_lines:bool -><br> ?ignore_inode_change:bool -><br> ?start_at:[ `Beginning | `End | `Pos of Core.Std.Int64.t ] -><br> ?eof_latency_tolerance:Core.Std.Time.Span.t -><br> ?null_read_tolerance:Core.Std.Time.Span.t -><br> string -> <a href="File_tail.Update.html#TYPEt">Update.t</a> Import.Pipe.Reader.t</code></pre><div class="info ">
<code class="code">create file</code> creates a <code class="code">File_tail.t</code> that will immediately begin reading <code class="code">file</code>, and
then will start the stat-read loop.
<p>
<code class="code">read_buf_len</code> sets the size of the internal buffer used for making read system calls.
<p>
<code class="code">read_delay</code> sets how long the stat-read loop waits each time after it reaches eof
before stat'ing again. Setting <code class="code">read_delay</code> too low could cause unecessary load.
<p>
If <code class="code">retry_null_reads = true</code>, then reads that return data with null ('\000')
characters are ignored and cause the system to delay 0.2s and attempt the read again.
If <code class="code">retry_null_reads = false</code>, then the file tail will process data with nulls just as
it would any other data.
<p>
If <code class="code">break_on_lines = true</code>, the file tail will break data into lines on '\n'. If not,
the fill tail will return chunks of data from the end of the file as they are
available.
<p>
If <code class="code">ignore_inode_change = true</code>, the file tail will silently press on when the
<code class="code">file</code>'s inode changes. If not, an inode change will cause the file tail to report an
error and stop. CIFS changes inodes of mounted files few times a day and we need
<code class="code">ignore_inode_change = true</code> option to keep tailers watching files on it alive.
<p>
<code class="code">start_at</code> determines the file position at which the file tail starts.
<p>
<code class="code">eof_latency_tolerance</code> affects the <code class="code">Did_not_reach_eof_for</code> warning.
<p>
<code class="code">null_read_tolerance</code> determines how long the tailing must observe null reads
before it will report a <code class="code">Delayed_due_to_null_reads_for</code> warning.<br>
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