Compile errors on V/386 3.0E

[Mark E. Mallett]

In article <273 at uport.UUCP> plocher at uport.UUCP (John Plocher) writes:
>In article <417 at zinn.MV.COM> mem at zinn.MV.COM (Mark E. Mallett) writes:
>>	extern	(*signal())();
>
>NO!
>
>In ATT System Vr3 (Microport's V/386 2.2 & 3.0e, ISC's 1.0x, BT's 3.0...)
>signal() was changed to be of type void.  This is different from almost
>everyone else (uugh!) but that's how AT&T did it.


"No" is right... as I've been told.  Except, of course, that I was
mostly describing out where the warnings came from and not so much
what the correct signal.h should have in it.  Although signal() is not
of type void, but of type ptr-to-function-returning-void.

(1)	extern void (*signal())();

looks like a better definition than the traditional

(2)	extern int (*signal())();

since in (1), signal() is defined to return a pointer to a routine that
doesn't return anything, and in (2) it returns a pointer to a routine
that returns an int.  Of course, umpty-ump thousands of programs that
use signal() as a (2) will now compile with warnings.  A small
price for perfection :-)


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