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< p > Library Version 11.2.5.3< / p >
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< th colspan = "3" align = "center" > DB_MPOOLFILE-> set_clear_len()< / th >
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The DB_MPOOLFILE Handle
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< h2 class = "title" style = "clear: both" > < a id = "mempset_clear_len" > < / a > DB_MPOOLFILE-> set_clear_len()< / h2 >
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< pre class = "programlisting" > #include < db.h>
int
DB_MPOOLFILE-> set_clear_len(DB_MPOOLFILE *mpf, u_int32_t len); < / pre >
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The < code class = "methodname" > DB_MPOOLFILE-> set_clear_len()< / code > method sets the number of initial
bytes in a page that should be set to nul when the page is created as
a result of the
< a class = "link" href = "mempfget.html#mpoolfget_DB_MPOOL_CREATE" > DB_MPOOL_CREATE< / a >
or < a class = "link" href = "mempfget.html#mpoolfget_DB_MPOOL_NEW" > DB_MPOOL_NEW< / a >
flags specified to < a class = "xref" href = "mempfget.html" title = "DB_MPOOLFILE->get()" > DB_MPOOLFILE-> get()< / a > . If no
clear length is specified, the entire page is cleared when it is
created.
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< p >
The < code class = "methodname" > DB_MPOOLFILE-> set_clear_len()< / code > method configures a file in the
cache, not only operations performed using the specified
< a class = "link" href = "memp.html" title = "Chapter > DB_MPOOLFILE< / a > handle.
< / p >
< p >
The < code class = "methodname" > DB_MPOOLFILE-> set_clear_len()< / code > method may not be called after the
< a class = "xref" href = "mempfopen.html" title = "DB_MPOOLFILE->open()" > DB_MPOOLFILE-> open()< / a >
method is called. If the file is already open in the cache when
< a class = "xref" href = "mempfopen.html" title = "DB_MPOOLFILE->open()" > DB_MPOOLFILE-> open()< / a > is
called, the information specified to < code class = "methodname" > DB_MPOOLFILE-> set_clear_len()< / code >
must be consistent with the existing file or an error will be returned.
< / p >
< p >
The < code class = "methodname" > DB_MPOOLFILE-> set_clear_len()< / code > < span >
< span >
method returns a non-zero error value on failure and 0 on success.
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< h4 class = "title" > < a id = "idp61533720" > < / a > len< / h4 >
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The < span class = "bold" > < strong > len< / strong > < / span > parameter is the number of
initial bytes in a page that should be set to nul when the page is
created. A value of 0 results in the entire page being set to nul
bytes.
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< h3 class = "title" > < a id = "idp61525376" > < / a > See Also< / h3 >
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< a class = "xref" href = "memp.html#memplist" title = "Memory Pools and Related Methods" > Memory Pools and Related Methods< / a >
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