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< p > Library Version 11.2.5.2< / p >
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< th colspan = "3" align = "center" > DB_ENV-> txn_checkpoint()< / th >
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< h2 class = "title" style = "clear: both" > < a id = "txncheckpoint" > < / a > DB_ENV-> txn_checkpoint()< / h2 >
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< pre class = "programlisting" > #include < db.h>
int
DB_ENV-> txn_checkpoint(const DB_ENV *env,
u_int32_t kbyte, u_int32_t min, u_int32_t flags); < / pre >
< p >
If there has been any logging activity in the database environment
since the last checkpoint, the < code class = "methodname" > DB_ENV-> txn_checkpoint()< / code > method
flushes the underlying memory pool, writes a checkpoint record to the
log, and then flushes the log.
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< p >
The < code class = "methodname" > DB_ENV-> txn_checkpoint()< / code > method returns a non-zero error value on
failure and 0 on success.
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The < code class = "methodname" > DB_ENV-> txn_checkpoint()< / code > method is the underlying method used by
the < a class = "link" href = "db_checkpoint.html" title = "db_checkpoint" > db_checkpoint< / a >
utility. See the < a class = "link" href = "db_checkpoint.html" title = "db_checkpoint" > db_checkpoint< / a > utility
source code for an example of using < code class = "methodname" > DB_ENV-> txn_checkpoint()< / code > in a
IEEE/ANSI Std 1003.1 (POSIX) environment.
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< h3 class = "title" > < a id = "id3759786" > < / a > Parameters< / h3 >
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< h4 class = "title" > < a id = "id3760644" > < / a > kbyte< / h4 >
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If the < span class = "bold" > < strong > kbyte< / strong > < / span > parameter is non-zero, a
checkpoint will be done if more than < span class = "bold" > < strong > kbyte< / strong > < / span > kilobytes of log data have been written
since the last checkpoint.
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< h4 class = "title" > < a id = "id3760877" > < / a > min< / h4 >
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If the < span class = "bold" > < strong > min< / strong > < / span > parameter is non-zero, a
checkpoint will be done if more than < span class = "bold" > < strong > min< / strong > < / span > minutes have passed since the last
checkpoint.
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< h4 class = "title" > < a id = "id3759694" > < / a > flags< / h4 >
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The < span class = "bold" > < strong > flags< / strong > < / span > parameter must be set to 0
or the following value:
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< code class = "literal" > DB_FORCE< / code >
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Force a checkpoint record, even if there has been no activity since
the last checkpoint.
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< h3 class = "title" > < a id = "id3760904" > < / a > Errors< / h3 >
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The < code class = "methodname" > DB_ENV-> txn_checkpoint()< / code > < span >
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method may fail and return one of the following non-zero errors:
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< h4 class = "title" > < a id = "id3760730" > < / a > EINVAL< / h4 >
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An invalid flag value or parameter was specified.
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< a class = "link" href = "env.html" title = "Chapter > DB_ENV< / a > , < a class = "link" href = "txn.html" title = "Chapter > DB_TXN< / a >
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< a class = "xref" href = "txn.html#txnlist" title = "Transaction Subsystem and Related Methods" > Transaction Subsystem and Related Methods< / a >
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