Path: utzoo!utgpu!jarvis.csri.toronto.edu!rutgers!cs.utexas.edu!uunet!mcvax!hp4nl!ctisbv!pim
From: pim@ctisbv.UUCP (Pim Zandbergen)
Newsgroups: news.software.b
Subject: Re: C news vs B news speed
Message-ID: <781@ctisbv.UUCP>
Date: 13 Jul 89 17:28:28 GMT
References: <1989Jul9.223927.29156@elroy.jpl.nasa.gov> <1989Jul12.210254.8631@utzoo.uucp>
Reply-To: pim@ctisbv.UUCP (Pim Zandbergen)
Organization: CTI Software BV, The Hague, The Netherlands
Lines: 49

In article <1989Jul12.210254.8631@utzoo.uucp> henry@utzoo.uucp (Henry Spencer) writes:

[ about rewriting spacefor in C ]

>I'm contemplating doing some of this myself, in fact, although if I do
>use C for spacefor, it will probably popen("df") to do the actual space
>finding -- that job is just too system-dependent.

The following works for me on
AT&T System V/386 r 3.2,
System V r 3.1.1 on the AT&T 3B2,
SCO Xenix,
Microport System V/AT,
AIX for the IBM PC RT.
_______________________________________________________________________________
#include	<sys/types.h>
#include	<sys/stat.h>
#include	<ustat.h>

main()
{
	struct stat	statbuf;
	struct ustat	ustatbuf;

	if (stat("/usr/spool/news", &statbuf) < 0)
	{
		perror("cannot fstat");
		exit(1);
	}
	if (ustat(statbuf.st_dev, &ustatbuf) < 0)
	{
		perror("cannot ustat");
		exit(1);
	}
	printf("%ld free blocks\n", (long)(ustatbuf.f_tfree));
	printf("%ld free inodes\n", (long)(ustatbuf.f_tinode));
}
_______________________________________________________________________________

It should be noted, however, that this program reports
the real number of free blocks, which is not necessarely
in 512 byte units. I know of no system call that reports
the blocksize of a filesystem *and* is present in all the
mentioned flavours of System V (no statfs(2) in AIX nor in uPort V/AT).
-- 
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