4.4BSD/usr/share/man/cat3f/traper.0

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TRAPER(3F)             BSD Reference Manual            TRAPER(3F)

mer's Manual
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       traper - trap arithmetic errors

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       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
       previous  state  is  restored  on return.  Therefore, this
       routine must be called _i_n_s_i_d_e  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 _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.

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       /usr/lib/libF77.a

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       signal(3C), signal(3F)


















4.2 Berkeley Distribution  June 5, 1993                         1