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Date: Sat, 26 Feb 2005 01:10:46 -0800 (PST)
From: Yan Yu <yanyu@CS.UCLA.EDU>
To: freebsd-hackers@freebsd.org
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Subject: confusion on fopen()/falloc() 
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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
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