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<div id="version" align=right><b>petsc-3.14.5 2021-03-03</b></div>
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<A NAME="PetscBinaryWrite"><H1>PetscBinaryWrite</H1></A>
Writes to a binary file.
<H3><FONT COLOR="#CC3333">Synopsis</FONT></H3>
<PRE>
<A HREF="../Sys/PetscErrorCode.html#PetscErrorCode">PetscErrorCode</A> <A HREF="../Sys/PetscBinaryWrite.html#PetscBinaryWrite">PetscBinaryWrite</A>(int fd,const void *p,<A HREF="../Sys/PetscInt.html#PetscInt">PetscInt</A> n,<A HREF="../Sys/PetscDataType.html#PetscDataType">PetscDataType</A> type)
</PRE>
Not Collective
<P>
<H3><FONT COLOR="#CC3333">Input Parameters</FONT></H3>
<TABLE border="0" cellpadding="0" cellspacing="0">
<TR><TD WIDTH=40></TD><TD ALIGN=LEFT VALIGN=TOP><B>fd </B></TD><TD>- the file
</TD></TR>
<TR><TD WIDTH=40></TD><TD ALIGN=LEFT VALIGN=TOP><B>p </B></TD><TD>- the buffer
</TD></TR>
<TR><TD WIDTH=40></TD><TD ALIGN=LEFT VALIGN=TOP><B>n </B></TD><TD>- the number of items to write
</TD></TR>
<TR><TD WIDTH=40></TD><TD ALIGN=LEFT VALIGN=TOP><B>type </B></TD><TD>- the type of items to read (<A HREF="../Sys/PetscDataType.html#PetscDataType">PETSC_INT</A>, <A HREF="../Sys/PetscDataType.html#PetscDataType">PETSC_DOUBLE</A> or PETSC_SCALAR)
</TD></TR></TABLE>
<P>
<P>
<H3><FONT COLOR="#CC3333">Notes</FONT></H3>
<A HREF="../Sys/PetscBinaryWrite.html#PetscBinaryWrite">PetscBinaryWrite</A>() uses byte swapping to work on all machines; the files
are written using big-endian ordering to the file. On little-endian machines the numbers
are converted to the big-endian format when they are written to disk.
When PETSc is ./configure with --with-64-bit-indices the integers are written to the
file as 64 bit integers, this means they can only be read back in when the option --with-64-bit-indices
is used.
<P>
If running with __float128 precision the output is in __float128 unless one uses the -binary_write_double option
<P>
The Buffer p should be read-write buffer, and not static data.
This way, byte-swapping is done in-place, and then the buffer is
written to the file.
<P>
This routine restores the original contents of the buffer, after
it is written to the file. This is done by byte-swapping in-place
the second time.
<P>
Because byte-swapping may be done on the values in data it cannot be declared const
<P>
<P>
<H3><FONT COLOR="#CC3333">See Also</FONT></H3>
<A HREF="../Sys/PetscBinaryRead.html#PetscBinaryRead">PetscBinaryRead</A>(), <A HREF="../Sys/PetscBinaryOpen.html#PetscBinaryOpen">PetscBinaryOpen</A>(), <A HREF="../Sys/PetscBinaryClose.html#PetscBinaryClose">PetscBinaryClose</A>(), <A HREF="../Viewer/PetscViewerBinaryGetDescriptor.html#PetscViewerBinaryGetDescriptor">PetscViewerBinaryGetDescriptor</A>(), <A HREF="../Sys/PetscBinarySynchronizedWrite.html#PetscBinarySynchronizedWrite">PetscBinarySynchronizedWrite</A>(),
<BR><A HREF="../Sys/PetscBinarySynchronizedRead.html#PetscBinarySynchronizedRead">PetscBinarySynchronizedRead</A>(), <A HREF="../Sys/PetscBinarySynchronizedSeek.html#PetscBinarySynchronizedSeek">PetscBinarySynchronizedSeek</A>()
<P><B></B><H3><FONT COLOR="#CC3333">Level</FONT></H3>advanced<BR>
<H3><FONT COLOR="#CC3333">Location</FONT></H3>
</B><A HREF="../../../src/sys/fileio/sysio.c.html#PetscBinaryWrite">src/sys/fileio/sysio.c</A>
<P><H3><FONT COLOR="#CC3333">Examples</FONT></H3>
<A HREF="../../../src/vec/vec/tutorials/ex6.c.html">src/vec/vec/tutorials/ex6.c.html</A><BR>
<A HREF="../../../src/vec/vec/tutorials/ex6f.F90.html">src/vec/vec/tutorials/ex6f.F90.html</A><BR>
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