4.3BSD-Reno/share/man/cat3f/traper.0
TRAPER(3F) 1985 TRAPER(3F)
NNAAMMEE
traper - trap arithmetic errors
SSYYNNOOPPSSIISS
iinntteeggeerr ffuunnccttiioonn ttrraappeerr ((mmaasskk))
DDEESSCCRRIIPPTTIIOONN
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oonn tthhee PPDDPP1111..
Integer overflow and floating point underflow are not nor-
mally 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 pre-
vious state is restored on return. Therefore, this routine
must be called _i_n_s_i_d_e each subprogram in which these condi-
tions should be trapped. If the condition occurs and trap-
ping is enabled, signal SIGFPE is sent to the process. (See
_s_i_g_n_a_l(3C))
The argument has the following meaning:
value meaning
0 do not trap either condition
1 trap integer overflow only
2 trap floating underflow only
3 trap both the above
The previous value of these bits is returned.
FFIILLEESS
/usr/lib/libF77.a
SSEEEE AALLSSOO
signal(3C), signal(3F)
Printed 7/27/90 May 1