Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.1 6/24/83; site utah-cs.UUCP Path: utzoo!watmath!clyde!burl!ulysses!allegra!mit-eddie!genrad!panda!talcott!harvard!seismo!utah-cs!donn From: donn@utah-cs.UUCP (Donn Seeley) Newsgroups: net.lang.f77 Subject: Re: (do) while loops Message-ID: <3505@utah-cs.UUCP> Date: Sun, 27-Oct-85 01:00:47 EST Article-I.D.: utah-cs.3505 Posted: Sun Oct 27 01:00:47 1985 Date-Received: Tue, 29-Oct-85 00:56:27 EST References: <144@oberon.UUCP> Organization: University of Utah CS Dept Lines: 27 From: mcooper@oberon.UUCP (Michael Cooper) My question is: doesn't Unix (ANSI) f77 support a (do) while statement? ... This is really two questions: (1) Does the ANSI standard define DO-WHILE loops (or '!' comments or DEFINE-FILE or zillions of I/O parameters or QIO calls)? Ans.: No. (2) Does Unix f77 support this? Ans.: Unix f77 compilers which are descendants of the original AT&T Feldman/Weinberger compiler support very few syntax extensions; in particular they recognize only the DO loop which is defined in the ANSI standard. Some manufacturers (Convex is one, I'm told; DEC, curiously, is not) advertise 'VMS-compatible' Unix compilers, which presumably accept DO-WHILE and other extensions. My perception is that these manufacturers are in the minority. Moral: if your VMS compiler has a flag to turn off non-ANSI extensions, use it or be prepared to use VMS forever. I'm not sure whether to blame the ANSI committee for not adopting these extensions or DEC for adding them (and I'm not familiar enough with the history of the standard to know whether these extensions were considered)... Fortran-8x will probably support QIO calls, Donn Seeley University of Utah CS Dept donn@utah-cs.arpa 40 46' 6"N 111 50' 34"W (801) 581-5668 decvax!utah-cs!donn