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We are trying to migrate an oracle database from Sun Solaris (SunOS 5.9 Generic_118558-28 sun4u sparc SUNW,Ultra-60) to Linux 2.6.18-53.1.19.el5 #1 SMP Tue Apr 22 03:01:10 EDT 2008 x86_64 x86_64 x86_64 GNU/Linux which is basically a Big Endian to Little Endian conversion.
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cvt_ftof
cvt_ftof(3) Library Functions Manual cvt_ftof(3)
NAME
cvt_ftof - Converts a floating-point data type to another supported floating-point data type.
LIBRARY
Math Library (libm.a)
SYNOPSIS
#include <cvt.h>
int cvt_ftof(
void *input_val,
int input_type,
void *output_val,
int output_type,
int options);
DESCRIPTION
cvt_ftof() converts one floating-point data type to another. Input_val points to the input value to be converted and output_val points to
the converted result. The conversion is subject to the options specified in the options (bit field) argument. This function returns a bit
field indicating any status conditions.
Input_type and output_type identify the floating-point data type of input_val and output_val as follows:
------------------------------------------------------------------
Input_type/Output_type Data Type Size
------------------------------------------------------------------
CVT_VAX_F VAX F Floating 4 bytes
CVT_VAX_D VAX D Floating 8 bytes
CVT_VAX_G VAX G Floating 8 bytes
CVT_VAX_H VAX H Floating 16 bytes
CVT_IEEE_S IEEE Little Endian S Floating 4 bytes
CVT_IEEE_T IEEE Little Endian T Floating 8 bytes
CVT_IEEE_X IEEE Little Endian X Floating 16 bytes
CVT_BIG_ENDIAN_IEEE_S IEEE Big Endian S Floating 4 bytes
CVT_BIG_ENDIAN_IEEE_T IEEE Big Endian T Floating 8 bytes
CVT_BIG_ENDIAN_IEEE_X IEEE Big Endian X Floating 16 bytes
CVT_IBM_SHORT IBM Short Floating 4 bytes
CVT_IBM_LONG IBM Long Floating 8 bytes
CVT_CRAY_SINGLE Cray Single Floating 8 bytes
------------------------------------------------------------------
Provide a zero (0) value to the options argument to select default behavior or choose one or more options (status condition option, round-
ing options, "FORCE" options, Cray and IBM options) from the tables below as the options argument. Specify only the options that apply to
your conversion. A conflicting or incompatible options argument will be reported as an error (CVT_INVALID_OPTION).
----------------------------------------------------------------------------
Applicable
Conversion Status Condition Option Description
----------------------------------------------------------------------------
All CVT_REPORT_ALL Report all applicable status condi-
tions as the default. The reporting
of recoverable status conditions is
disabled by default when this option
is not used.
----------------------------------------------------------------------------
-------------------------------------------------------------------------
Applicable
Conversion Rounding Options Description
-------------------------------------------------------------------------
All CVT_ROUND_TO_NEAREST The default rounding mode for con-
versions to IEEE data types. This
IEEE Std. 754 rounding mode results
in a representable output value
nearest to the infinitely precise
result. If the two nearest repre-
sentable values are equally near,
the one with its least significant
bit zero is the result.
All CVT_BIASED_ROUNDING The default rounding mode for con-
versions to non-IEEE data types.
Performs "traditional" style round-
ing. This mode results in a repre-
sentable output value nearest to the
infinitely precise result. If the
two nearest representable values are
equally near, the output value is
the closest to either positive
infinity or negative infinity
depending on the sign of the input
value.
All CVT_ROUND_TO_ZERO Round the output value toward zero
(truncate).
All CVT_ROUND_TO_POS Round the output value toward posi-
tive infinity.
All CVT_ROUND_TO_NEG Round the output value toward nega-
tive infinity.
-------------------------------------------------------------------------
-----------------------------------------------------------------------------------
Applicable
Conversion "FORCE" Options Description
-----------------------------------------------------------------------------------
All CVT_FORCE_ALL_SPECIAL_VALUES Apply all applicable "FORCE" options
for the current conversion.
IEEE CVT_FORCE_DENORM_TO_ZERO Force a denormalized IEEE output
value to zero. This option is valid
only for conversions to IEEE output
values.
IEEE CVT_FORCE_INF_TO_MAX_FLOAT Force a positive IEEE infinite out-
put value to +max_float and force a
negative IEEE infinite output value
to -max_float. This option is valid
only for conversions to IEEE output
values.
IEEE or VAX CVT_FORCE_INVALID_TO_ZERO Force an invalid IEEE NaN (not a
number) output value or a VAX ROP
(reserved operand) output value to
zero. This option is valid only for
conversions to IEEE or VAX output
values.
-----------------------------------------------------------------------------------
----------------------------------------------------------------------------------------
Applicable
Conversion Options for Cray Format Conversion Description
----------------------------------------------------------------------------------------
Cray CVT_ALLOW_OVRFLW_RANGE_VALUES Allow an input/output exponent value
> 60000 (8).
Cray CVT_ALLOW_UDRFLW_RANGE_VALUES Allow an input/output exponent value
< 20000 (8).
----------------------------------------------------------------------------------------
----------------------------------------------------------------------------------------
Applicable
Conversion Options for IBM Format Conversion Description
----------------------------------------------------------------------------------------
IBM CVT_ALLOW_UNNORMALIZED_VALUES Allow unnormalized input arguments.
Allow an unnormalized output value
for a small value which would nor-
malize to zero.
----------------------------------------------------------------------------------------
The maximum representable floating-point values (max_float) for the IEEE_S_Floating, IEEE_T_Floating, IEEE_X_Floating,
Big_Endian_IEEE_S_Floating, Big_Endian_IEEE_T_Floating, and Big_Endian_IEEE_X_Floating formats are:
---------------------------------------------------------------------------
Data Type max_float Value
---------------------------------------------------------------------------
S_FLOAT Decimal: 3.402823e38
T_FLOAT Decimal: 1.797693134862316e308
X_FLOAT Decimal: 1.189731495357231765085759326628007016196477e4932
---------------------------------------------------------------------------
EXAMPLES
This example converts the value pointed to by big_x which is of type IEEE Big Endian T Floating, to the IEEE Little Endian T Floating
data type and stores the result in the location pointed to by little_x. No conversion options are specified.
status = cvt_ftof( &big_x, CVT_BIG_ENDIAN_IEEE_T,
&little_x, CVT_IEEE_T, 0 );
This example converts the value pointed to by x which is of type VAX D Floating, to the IEEE Little Endian T Floating data type and
stores the result in the location pointed to by y. Any special IEEE values which would normally be generated will be removed.
That is, NaN and Denormalized results will be returned as zero and infinite results will go to +- max_float. In addition, all record-
able status conditions will be reported.
status = cvt_ftof(&x, CVT_VAX_D, &y, CVT_IEEE_T,
(CVT_FORCE_ALL_SPECIAL_VALUES | CVT_REPORT_ALL) );
RETURN VALUES
The return value is a bit field containing the condition codes raised by the function. cvt_ftof() returns CVT_NORMAL; otherwise, it sets
one or more of the following recoverable and unrecoverable conditions. Use the following condition names to determine which conditions are
set:
------------------------------------------------------------------
Condition Name Condition (Always reported by default)
------------------------------------------------------------------
CVT_INVALID_INPUT_TYPE Invalid input type code.
CVT_INVALID_OUTPUT_TYPE Invalid output type code.
CVT_INVALID_OPTION Invalid option argument.
------------------------------------------------------------------
-----------------------------------------------------------------
Condition (Only reported if the
Condition Name CVT_REPORT_ALL option is selected)
-----------------------------------------------------------------
CVT_RESULT_INFINITE Conversion produced an infinite
result. (For conversions to IEEE
data types.)
CVT_RESULT_DENORMALIZED Conversion produced a denormalized
result. (For conversions to IEEE
data types.)
CVT_RESULT_OVERFLOW_RANGE Conversion yielded an exponent >
60000 (8). (For Cray data type
conversions.)
CVT_RESULT_UNDERFLOW_RANGE Conversion yielded an exponent <
20000 (8). (For Cray data type
conversions.)
CVT_RESULT_UNNORMALIZED Conversion produced an unnormal-
ized result. (For IBM data type
conversions and reported
CVT_RESULT_INVALID Conversion result is either ROP
(reserved operand), NaN (not a
number), or closest equivalent.
Cray and IBM data types return 0.
(For all data type conversions.)
CVT_RESULT_OVERFLOW Conversion resulted in overflow.
(For all data type conversions.)
CVT_RESULT_UNDERFLOW Conversion resulted in underflow.
(For all data type conversions.)
CVT_RESULT_INEXACT Conversion resulted in a loss of
precision. (For all data type
conversions.)
-----------------------------------------------------------------
RELATED INFORMATION
ANSII/IEEE Std 754-1985, IEEE Standard for Binary Floating-Point Arithmetic delim off
cvt_ftof(3)
