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econvert(3)

sigfpe(3)

abort(3)

strtod(3)



floatingpoint(3)       C LIBRARY FUNCTIONS       floatingpoint(3)



NAME
     floatingpoint - IEEE floating point definitions

SYNOPSIS
     cc [ flag... ] file ... -lucb
     #include <sys/ieeefp.h>
     #include <fp.h>

DESCRIPTION
     This file defines constants, types, variables, and functions
     used  to  implement  standard  floating  point  according to
     ANSI/IEEE Std 754-1985.  The  variables  and  functions  are
     implemented  in  libucb.a.  The included file <sys/ieeefp.h>
     defines certain types  of  interest  to  the  kernel.   IEEE
     Rounding Modes:

     fpdirectiontype   The type of the IEEE rounding  direction
                         mode.   Note:  the  order of enumeration
                         varies according to hardware.

     fpdirection        The   IEEE   rounding   direction   mode
                         currently  in  force.   This is a global
                         variable that is intended to reflect the
                         hardware  state,  so  it  should only be
                         written indirectly  through  a  function
                         that also sets the hardware state.

     fpprecisiontype   The type of the IEEE rounding  precision
                         mode, which only applies on systems that
                         support extended precision.

     fpprecision        The   IEEE   rounding   precision   mode
                         currently  in  force.   This is a global
                         variable that is intended to reflect the
                         hardware  state on systems with extended
                         precision, so it should only be  written
                         indirectly.  SIGFPE handling:

     sigfpecodetype    The type of a SIGFPE code.

     sigfpehandlertype The  type  of  a  user-definable  SIGFPE
                         exception  handler  called  to  handle a
                         particular SIGFPE code.

     SIGFPEDEFAULT      A macro indicating  the  default  SIGFPE
                         exception  handling,  namely  to perform
                         the  exception  handling  specified   by
                         calls  to  ieeehandler(3M), if any, and
                         otherwise to dump core using abort(3).

     SIGFPEIGNORE       A macro indicating an  alternate  SIGFPE
                         exception handling, namely to ignore and



             Last change: BSD Compatibility Package             1





floatingpoint(3)       C LIBRARY FUNCTIONS       floatingpoint(3)



                         continue execution.

     SIGFPEABORT        A macro indicating an  alternate  SIGFPE
                         exception handling, namely to abort with
                         a core dump.  IEEE Exception Handling:

     NIEEEEXCEPTION    The number of  distinct  IEEE  floating-
                         point exceptions.

     fpexceptiontype   The type of the NIEEEEXCEPTION  excep-
                         tions.   Each  exception  is given a bit
                         number.

     fpexceptionfieldtype
                         The  type  intended  to  hold  at  least
                         NIEEEEXCEPTION  bits  corresponding to
                         the   IEEE   exceptions   numbered    by
                         fpexceptiontype.     Thus   fpinexact
                         corresponds to the least significant bit
                         and fpinvalid to the fifth least signi-
                         ficant bit.  Note: some  operations  may
                         set more than one exception.

     fpaccruedexceptions
                         The IEEE  exceptions  between  the  time
                         this  global  variable was last cleared,
                         and the last time a function was  called
                         to  update the variable by obtaining the
                         hardware state.

     ieeehandlers       An  array  of  user-specifiable   signal
                         handlers  for use by the standard SIGFPE
                         handler  for   IEEE   arithmetic-related
                         SIGFPE codes.  Since IEEE trapping modes
                         correspond to hardware  modes,  elements
                         of  this  array  should only be modified
                         with a  function  like  ieeehandler(3M)
                         that  performs  the appropriate hardware
                         mode update.  If no  sigfpehandler  has
                         been  declared  for  a  particular IEEE-
                         related SIGFPE code,  then  the  related
                         ieeehandlers  will  be  invoked.   IEEE
                         Formats and Classification:

     single;extended     Definitions of IEEE formats.

     fpclasstype       An enumeration of the various classes of
                         IEEE  values  and  symbols.   IEEE  Base
                         Conversion:

                         The    functions     described     under
                         floatingtodecimal(3)               and



             Last change: BSD Compatibility Package             2





floatingpoint(3)       C LIBRARY FUNCTIONS       floatingpoint(3)



                         decimaltofloating(3) not only  satisfy
                         the IEEE Standard, but also the stricter
                         requirements of correct rounding for all
                         arguments.

     DECIMALSTRINGLENGTH
                         The length of a decimalstring.

     decimalstring      The digit buffer in a decimalrecord.

     decimalrecord      The canonical form for  representing  an
                         unpacked decimal floating-point number.

     decimalform        The type used to specify fixed or float-
                         ing binary to decimal conversion.

     decimalmode        A struct  that  contains  specifications
                         for   conversion   between   binary  and
                         decimal.

     decimalstringform An enumeration of possible valid charac-
                         ter  strings representing floating-point
                         numbers, infinities, or NaNs.

FILES
     /usr/include/sys/ieeefp.h
     /usr/include/fp.h
     /usr/ucblib/libucb.a

SEE ALSO
     decimaltofloating(3), econvert(3), floatingtodecimal(3),
     ieeehandler(3M), sigfpe(3).  abort(3), strtod(3) in the
     Programmer's Reference Manual.






















             Last change: BSD Compatibility Package             3



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