(recode.info)Test

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Artificial data for testing
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   A few pseudo-surfaces exist to generate debugging data out of thin
air.  These surfaces are only meant for the expert `recode' user, and
are only useful in a few contexts, like for generating binary
permutations from the recoding or acting on them.

   Debugging surfaces, _when removed_, insert their generated data at
the beginning of the output stream, and copy all the input stream after
the generated data, unchanged.  This strange removal constraint comes
from the fact that debugging surfaces are usually specified in the
_before_ position instead of the _after_ position within a request.
With debugging surfaces, one often recodes file `/dev/null' in filter
mode.  Specifying many debugging surfaces at once has an accumulation
effect on the output, and since surfaces are removed from right to left,
each generating its data at the beginning of previous output, the net
effect is an _impression_ that debugging surfaces are generated from
left to right, each appending to the result of the previous.  In any
case, any real input data gets appended after what was generated.

`test7'
     When removed, this surface produces 128 single bytes, the first
     having value 0, the second having value 1, and so forth until all
     128 values have been generated.

`test8'
     When removed, this surface produces 256 single bytes, the first
     having value 0, the second having value 1, and so forth until all
     256 values have been generated.

`test15'
     When removed, this surface produces 64509 double bytes, the first
     having value 0, the second having value 1, and so forth until all
     values have been generated, but excluding risky `UCS-2' values,
     like all codes from the surrogate `UCS-2' area (for `UTF-16'), the
     byte order mark, and values known as invalid `UCS-2'.

`test16'
     When removed, this surface produces 65536 double bytes, the first
     having value 0, the second having value 1, and so forth until all
     65536 values have been generated.

   As an example, the command `recode l5/test8..dump < /dev/null' is a
convoluted way to produce an output similar to `recode -lf l5'.  It says
to generate all possible 256 bytes and interpret them as `ISO-8859-9'
codes, while converting them to `UCS-2'.  Resulting `UCS-2' characters
are dumped one per line, accompanied with their explicative name.