ANSI C standard library

Walter Bright bright at nazgul.UUCP
Sat Apr 27 07:31:19 AEST 1991


In article <681 at taumet.com> steve at taumet.com (Stephen Clamage) writes:
/In the full posting you mentioned only setjmp and longjmp as
/functions which cannot be written in strictly-conforming C, and
/memmove which cannot be written efficiently in strictly-conforming C.
/Can you name any other functions in the standard C library which
/cannot reasonably be written in strictly-conforming C.

Off the top of my head:
	malloc and friends, because implementation dependent details
	about pointer alignment need to be known.

	Any stdio functions, because they need to call operating system
	functions which aren't part of ANSI C.

	Any other functions which interface to the operating system,
	like time().

	Transcendental functions could be implemented, but would be
	inaccurate and slow if the mechanics of the underlying
	floating point were not taken advantage of.

	The startup code.

	The ctype.h functions, because they need to know if the
	implementation is ascii or some other scheme.

	The stdarg.h functionality.



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