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<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML3.2 EN">
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<TITLE>PetscBinaryWrite</TITLE>
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<A NAME="PetscBinaryWrite"><H1>PetscBinaryWrite</H1></A>
Writes to a binary file.
<H3><FONT COLOR="#CC3333">Synopsis</FONT></H3>
<PRE>
#include "petscsys.h"
PetscErrorCode PetscBinaryWrite(int fd,void *p,PetscInt n,PetscDataType type,PetscTruth 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.
Integers are stored on the file as 32 bits long, regardless of whether
they are stored in the machine as 32 bits or 64 bits, this means the same
binary file may be read on any machine. It also means that 64 bit integers larger than
roughly 2 billion are TRUNCATED/WRONG when written to the file.
<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 corrupted is corrupted.
<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>()
<BR><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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