Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Path: utzoo!watmath!clyde!rutgers!ames!ucbcad!ucbvax!levy@ucbvax.Berkeley.EDU@ttrdc.UUCP
From: levy@ucbvax.Berkeley.EDU@ttrdc.UUCP
Newsgroups: mod.computers.vax
Subject: (none)
Message-ID: <8701251759.AA15198@ucbvax.Berkeley.EDU>
Date: Sun, 25-Jan-87 12:59:19 EST
Article-I.D.: ucbvax.8701251759.AA15198
Posted: Sun Jan 25 12:59:19 1987
Date-Received: Wed, 28-Jan-87 06:51:32 EST
Sender: daemon@ucbvax.BERKELEY.EDU
Organization: The ARPA Internet
Lines: 32
Approved: info-vax@sri-kl.arpa

In article <870120220430.0a4@CitHex.Caltech.Edu>, carl@CITHEX.CALTECH.EDU.UUCP writes:
>Now, "text" files tend to:
>	1) Not be directories;
>	2) Have a record format of either variable length or some sort of
>	   stream records;
>	3) Belong to files organized sequentially;
>	4) Have PRINT, FORTRAN, or IMPLIED (CARRIAGE-RETURN) carriage control
>	   attributes, and the blocks are generally allowed to cross block
>	   boundaries.
>Checking these fields in the stat structure will come about as close as
>you can come to deciding whether you're dealing with a "text" file or a 
>binary file without resorting to something like:
>	1) Checking a few of the leading records of the file to discover
>	   whether they conform to the formats of, say executable, object,
>	   or library files; or
>	2) Running the thing through a dictionary so see if it has may
>	   recognizable words in it.

Why look for "words"?  Simply checking for non-ASCII characters would suffice,
which could even be done on the fly while reading the file into the applica-
ion program (editor, I believe it was).  This is presuming, as you suggest, that
the file attributes support the plausibility of the file being a text file.
(Note--an overly long maximum record length could be used to rule out the
possibility of a "text file" too.)

 -------------------------------    Disclaimer:  The views contained herein are
|            dan levy            |  my own and are not at all those of my em-
|         an engihacker @        |  ployer or the administrator of any computer
| at&t computer systems division |  upon which I may hack.
|        skokie, illinois        |
 --------------------------------   Path: ..!{akgua,homxb,ihnp4,ltuxa,mvuxa,
                                        allegra,ulysses,vax135}!ttrdc!levy