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<div id="version" align=right><b>petsc-3.7.5 2017-01-01</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>
PetscErrorCode PetscBinaryWrite(int fd,void *p,PetscInt n,PetscDataType type,PetscBool istemp)
</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 (PETSC_INT, PETSC_DOUBLE or PETSC_SCALAR)
</TD></TR>
<TR><TD WIDTH=40></TD><TD ALIGN=LEFT VALIGN=TOP><B>istemp </B></TD><TD>- <A HREF="../Sys/PETSC_FALSE.html#PETSC_FALSE">PETSC_FALSE</A> if buffer data should be preserved, <A HREF="../Sys/PETSC_TRUE.html#PETSC_TRUE">PETSC_TRUE</A> otherwise.
</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 small-endian machines the numbers
are converted to the big-endian format when they are written to disk.
When PETSc is ./configure with --with-64bit-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-64bit-indices
is used.
<P>
If running with __float128 precision the output is in __float128 unless one uses the -binary_read_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. If the flag istemp is set to <A HREF="../Sys/PETSC_TRUE.html#PETSC_TRUE">PETSC_TRUE</A>, the second
byte-swapping operation is not done, thus saving some computation,
but the buffer is left corrupted.
<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><P><B><FONT COLOR="#CC3333">Level:</FONT></B>advanced
<BR><FONT COLOR="#CC3333">Location:</FONT></B><A HREF="../../../src/sys/fileio/sysio.c.html#PetscBinaryWrite">src/sys/fileio/sysio.c</A>
<BR><A HREF="./index.html">Index of all Sys routines</A>
<BR><A HREF="../../index.html">Table of Contents for all manual pages</A>
<BR><A HREF="../singleindex.html">Index of all manual pages</A>
<P><H3><FONT COLOR="#CC3333">Examples</FONT></H3>
<A HREF="../../../src/vec/vec/examples/tutorials/ex6.c.html">src/vec/vec/examples/tutorials/ex6.c.html</A><BR>
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