Difference between revisions of "Null flush"

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(make it actually work)
 
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cat <(echo -e "this here[][\n]\0is a[][\n]\0little[][\n]\0flushing test[][\n]\0") /dev/stdin | your -z | pipe -z | goes -z | here -z
cat <(echo -e "this here[][\n]\0is a[][\n]\0little[][\n]\0flushing test[][\n]\0") /dev/stdin | your -z | pipe -z | goes -z | here -z
</pre>
</pre>
where \0 are the nulls, and the [] are there because many of the tools expect a [][\n] at the end of a stream (all the deformatters put this at the end of the stream). Use Ctrl-D (^D) to close the input that cat keeps open.
where \0 are the nulls, and the [] are there because many of the tools expect a [][\n] at the end of a stream (all the deformatters put this at the end of the stream, try <tt>echo bunnymen|apertium-destxt</tt>). Use Ctrl-D (^D) to close the input that cat keeps open.

=== Other flush signals ===
Note that in CG stream format, <code>vislcg3</code> uses the string "&lt;STREAMCMD:FLUSH&gt;" instead of a NUL byte: http://beta.visl.sdu.dk/cg3/single/#cmd-flush
(cg-proc, however, uses the NUL byte like the other programs used in Apertium).


[[Category:Terminology]]
[[Category:Terminology]]
[[Category:Documentation in English]]

Latest revision as of 18:29, 18 October 2016

Null flush is an option (-z) to most Apertium programs (and programs compatible with Apertium stream format) that flushes the output buffer upon receiving the \0 character instead of on end-of-file. This allows programs which call Apertium externally to keep a translator online, meaning they can avoid startup time for every translation.

To see how to use this in practice, read Daemon.

Testing[edit]

If you want to test that a pipe handles null flush correctly, you can use something like:

cat <(echo -e "this here[][\n]\0is a[][\n]\0little[][\n]\0flushing test[][\n]\0") /dev/stdin | your -z | pipe -z | goes -z | here -z

where \0 are the nulls, and the [] are there because many of the tools expect a [][\n] at the end of a stream (all the deformatters put this at the end of the stream, try echo bunnymen|apertium-destxt). Use Ctrl-D (^D) to close the input that cat keeps open.

Other flush signals[edit]

Note that in CG stream format, vislcg3 uses the string "<STREAMCMD:FLUSH>" instead of a NUL byte: http://beta.visl.sdu.dk/cg3/single/#cmd-flush (cg-proc, however, uses the NUL byte like the other programs used in Apertium).