From owner-freebsd-hackers@FreeBSD.ORG  Sat Feb 26 09:12:22 2005
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Date: Sat, 26 Feb 2005 01:12:22 -0800 (PST)
From: Yan Yu <yanyu@CS.UCLA.EDU>
To: freebsd-hackers@freebsd.org
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Subject: Re: confusion on fopen()/falloc() 
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On Sat, 26 Feb 2005, Yan Yu wrote:

> Hello, all,
> I have a user program as below:
> FILE *fd;
> while (1)
> {
> 	fd= fopen( "tmp", "r" );
> 	if ( fd == NULL )
> 		break;
> }
>
> from my understanding, since i open the same file to read, my process
> should create a new file descriptor each time when fopen is called.
> Therefore, inside the kernel, fdalloc() should be called, NOT falloc()
> (since falloc() allocates a new FILE * struct in addition to a new file
oops, what i really meant is a new FILE struct...


> descriptor),
> BUT based on what i observed (i instrumented falloc() function), it seems
> that falloc() is called each time when fopen() is called.
> I am wondering where i missed?
>
> Any hints is appreciated!
> Best,
> yan
>
>