Path: utzoo!utgpu!water!watmath!clyde!att!osu-cis!tut.cis.ohio-state.edu!ukma!uflorida!novavax!hcx1!hcx3!shirono
From: shirono@hcx3.SSD.HARRIS.COM
Newsgroups: comp.lang.c
Subject: Re: Xenix
Message-ID: <44100013@hcx3>
Date: 19 Sep 88 16:07:00 GMT
References: <171@uniblab.UUCP>
Lines: 31
Nf-ID: #R:uniblab.UUCP:171:hcx3:44100013:000:1321
Nf-From: hcx3.SSD.HARRIS.COM!shirono    Sep 19 12:07:00 1988


/* Written  3:10 pm  Sep 15, 1988 by chip@ateng.UUCP in hcx3:comp.lang.c */
According to english@stromboli.usc.edu (Joe English):
>In article <171@uniblab.UUCP> al@uniblab.UUCP (alan krantz) writes:
>> If i have an open file and want to set that files length
>> to zero, do i have to close the file and reopen it?
>
>Can't be done; you do have to close() and re- creat() or 
>open(... | O_TRUNC).

	int fd1, fd2;

	fd1 = creat("filename", 0666);
	write(fd1, "howdy", 5);
	fd2 = creat("filename", 0666);  /* truncates file */
	close(fd2);
	/* but fd1 is still open and available */
/* End of text from hcx3:comp.lang.c */

Also, fd1 is at offset 5.  The next write would happen at that point, leaving
a hole (or ASCII nul's).

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