1TRAPOV(3F)                                                          TRAPOV(3F)
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NAME

6       trapov - trap and repair floating point overflow
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SYNOPSIS

9       subroutine trapov (numesg, rtnval)
10       double precision rtnval
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DESCRIPTION

13       NOTE: This routine applies only to the older VAX 11/780's.  VAX comput‐
14       ers made or upgraded since spring 1983 handle errors differently.   See
15       trpfpe(3F)  for  the newer error handler.  This routine has always been
16       ineffective on the VAX 11/750.  It is a null routine on the PDP11.
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18       This call sets up signal handlers to trap arithmetic exceptions and the
19       use  of  illegal  operands.   Trapping arithmetic exceptions allows the
20       user's program to proceed from instances of floating point overflow  or
21       divide  by  zero.   The  result  of  such operations will be an illegal
22       floating point value.  The subsequent use of the illegal  operand  will
23       be trapped and the operand replaced by the specified value.
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25       The  first numesg occurrences of a floating point arithmetic error will
26       cause a message to be written to  the  standard  error  file.   If  the
27       resulting  value  is  used, the value given for rtnval will replace the
28       illegal operand generated by the arithmetic error.  Rtnval  must  be  a
29       double precision value. For example, ``0d0'' or ``dflmax()''.
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FILES

32       /usr/lib/libF77.a
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SEE ALSO

35       trpfpe(3F), signal(3F), range(3F)
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BUGS

38       Other arithmetic exceptions can be trapped but not repaired.
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40       There  is  no  way to distinguish between an integer value of 32768 and
41       the illegal floating point form.  Therefore such an integer  value  may
42       get replaced while repairing the use of an illegal operand.
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464.2 Berkeley Distribution        May 15, 1985                       TRAPOV(3F)