Path: utzoo!mnetor!uunet!sdrc!scjones
From: scjones@sdrc.UUCP (Larry Jones)
Newsgroups: comp.os.vms
Subject: Re: Bug in VAX C Run-Time Library
Message-ID: <209@sdrc.UUCP>
Date: 10 Feb 88 02:33:02 GMT
References: <880126085340.21e04d69@Csa2.LBL.Gov>
Organization: Structural Dynamics Research Corp., Cincinnati
Lines: 28

In article <880126085340.21e04d69@Csa2.LBL.Gov>, forrest@LBL.GOV writes:
> 
> What I'm doing is reading records from a file. If I use
> ftell to tell me where a certain record is located and then
> use fseek to go back to the record, I find that the next
> record differs depending on if the input file is a
> stream or a variable record file.

I too have had this problem from day 1 with VAX C.  The problem seems to be
that ftell on a record file just gets the current record number out of the
FAB (or RAB, or whereever the heck RMS keeps it).  Unfortunately, you aren't
actually in a record until you read at least one character from it, so the
"official" method of using fgets() doesn't help at all - you still haven't
read any of the next record so you still get the previous one.

As fas as suggestions, I have but two, neither of which is particularly
nice:

1)  Don't use record files.

2)  Do un ungetc(getc(file), file); just before the ftell().
-- 

----
Larry Jones                         UUCP: uunet!sdrc!scjones
SDRC                                MAIL: 2000 Eastman Dr., Milford, OH  45150
                                    AT&T: (513) 576-2070
"When all else fails, read the directions."