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From: dbj.rice%rand-relay@sri-unix.UUCP
Newsgroups: net.unix-wizards
Subject: Re: MAX FILES PER PROCESS PROBLEM
Message-ID: <13827@sri-arpa.UUCP>
Date: Sat, 19-Nov-83 22:35:49 EST
Article-I.D.: sri-arpa.13827
Posted: Sat Nov 19 22:35:49 1983
Date-Received: Tue, 22-Nov-83 03:26:51 EST
Lines: 16

From:  Dave Johnson <dbj.rice@rand-relay>

Under 4.1bsd, you can not make NOFILE greater than 31 thanks to the vread
and vwrite system calls.  In the page table entry for a vread page, there
is a 5-bit wide field called pg_fileno which is set to the file descriptor
number that the page is mapped from.  That is the meaning of the comment:

    #define	NOFILE	20		/* max open files per process */
    /* NOFILE MUST NOT BE >= 31; SEE pte.h */

from param.h where NOFILE is defined.

                                        Dave Johnson
                                        Dept. of Math Science
                                        Rice University
                                        dbj.rice@CSNet-Relay