Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!uflorida!novavax!twwells!bill
From: bill@twwells.uucp (T. William Wells)
Newsgroups: comp.unix.wizards
Subject: Re: How can a file be truncated on System V??
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Message-ID: <887@twwells.uucp>
Date: 29 Apr 89 20:16:44 GMT
References: <651@mitisft.Convergent.COM>
Reply-To: bill@twwells.UUCP (T. William Wells)
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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)

: that takes a file pointed at by fd and truncates the file to length bytes.
: The file descriptor may be only open for writing (which rules out dumping
: length bytes to a temporary file and copying them back, which involves
: read access).  How would one implement such a function in System V (I have
: tried the obvious ways, ie fcntl(), etc).  Do you have to write something
: to edit the inode to do this??

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.

---
Bill                            { uunet | novavax } !twwells!bill