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signal(3C)

signal(3F)

TRAPER(3F)  —  

NAME

traper − trap arithmetic errors

SYNOPSIS

integer function traper (mask)

DESCRIPTION

NOTE: This routine is a null routine.  IEEE default exception handling automatically provides an appropriate return value for exceptional operations.  Fpecount always returns zero.  What follows is the text of the original man page dated 18 July 1983. 

NOTE: This routine applies only to the VAX.  It is ignored on the PDP11. 

Integer overflow and floating point underflow are not normally trapped during execution. This routine enables these traps by setting status bits in the process status word. These bits are reset on entry to a subprogram, and the previous state is restored on return.  Therefore, this routine must be called inside each subprogram in which these conditions should be trapped.  If the condition occurs and trapping is enabled, signal SIGFPE is sent to the process. (See signal(3C))

The argument has the following meaning:

 Value   Meaning
 0Do not trap either condition
1Trap integer overflow only
2Trap floating underflow only
3Trap both the above
 

The previous value of these bits is returned. 

FILES

/usr/lib/libF77.a

SEE ALSO

signal(3C), signal(3F)

PRPQs 5799-WZQ/5799-PFF: IBM/4.3  —  July 1987

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