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From: allbery@ncoast.ORG (Brandon S. Allbery)
Newsgroups: comp.unix.wizards
Subject: Re: How can a file be truncated on System V??
Message-ID: <13619@ncoast.ORG>
Date: 6 May 89 16:43:07 GMT
References: <651@mitisft.Convergent.COM> <887@twwells.uucp>
Reply-To: allbery@ncoast.UUCP (Brandon S. Allbery)
Organization: Cleveland Public Access UN*X, Cleveland, Oh
Lines: 30

As quoted from <887@twwells.uucp> by bill@twwells.uucp (T. William Wells):
+---------------
| In article <651@mitisft.Convergent.COM> kemnitz@mitisft.Convergent.COM (Gregory Kemnitz) writes:
| : There is an ULTRIX (I think) function
| :
| : ftruncate(fd, length)
| : int fd, length;
| 
| (Actually, BSD)
| 
| You don't do it with a standard system call. I once had occasion to
| look long and hard for this and didn't find it.
+---------------

Standard System V (except perhaps 3.2) doesn't have this.  Xenix System V
may use one of two methods:

(1) zero-length write at point of truncation
(2) a system call whose name I've forgotten which truncates the file at
    the current lseek() position

SysV 3.2 probably uses the latter method.  I can look up the syscall if
you're desperate.

++Brandon
-- 
Brandon S. Allbery, moderator of comp.sources.misc	     allbery@ncoast.org
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