From 447c53e02a47dc8d479fbd426aead12fc30f277c Mon Sep 17 00:00:00 2001
From: Kirk McKusick <mckusick@ucbvax.Berkeley.EDU>
Date: Thu, 9 May 1985 23:03:20 -0800
Subject: [PATCH] manual page distributed with 4.2BSD

SCCS-vsn: lib/libc/sys/close.2 5.1
---
 usr/src/lib/libc/sys/close.2 | 96 +++++++++++++++++++++---------------
 1 file changed, 57 insertions(+), 39 deletions(-)

diff --git a/usr/src/lib/libc/sys/close.2 b/usr/src/lib/libc/sys/close.2
index 7263d887b0..d9e7f159ef 100644
--- a/usr/src/lib/libc/sys/close.2
+++ b/usr/src/lib/libc/sys/close.2
@@ -2,51 +2,69 @@
 .\" All rights reserved.  The Berkeley software License Agreement
 .\" specifies the terms and conditions for redistribution.
 .\"
-.\"	@(#)close.2	4.1 (Berkeley) %G%
+.\"	@(#)close.2	5.1 (Berkeley) %G%
 .\"
-.TH CLOSE 2 
+.TH CLOSE 2 "27 July 1983"
 .UC 4
 .SH NAME
-close \- close a file
+close \- delete a descriptor
 .SH SYNOPSIS
-.B close(fildes)
+.B close(d)
+.br
+.B "int d;"
 .SH DESCRIPTION
-Given
-a file descriptor such as returned from an
-.I open,
-.I creat,
-.I dup
-or
-.IR pipe (2)
-call,
-.I close
-closes the associated file.
-A close of all files is automatic on
-.I exit,
+The
+\fIclose\fP call deletes a descriptor from the per-process object
+reference table.
+If this is the last reference to the underlying object, then
+it will be deactivated.
+For example, on the last close of a file
+the current \fIseek\fP pointer associated with the file is lost;
+on the last close of a
+.IR socket (2)
+associated naming information and queued data are discarded;
+on the last close of a file holding an advisory lock
+the lock is released; see further
+.IR flock (2).
+.PP
+A close of all of a process's descriptors is automatic on
+.IR exit ,
 but since
-there is a limit on the number of open files per process,
+there is a limit on the number of active descriptors per process,
 .I close
-is necessary for programs which deal with many files.
+is necessary for programs which deal with many descriptors.
 .PP
-Files are closed upon termination of a process, and
-certain high-numbered file descriptors are closed by
-.IR exec (2),
-and it is possible to arrange for others to be closed
-(see FIOCLEX in
-.IR ioctl (2)).
+When a process forks (see
+.IR fork (2)),
+all descriptors for the new child process reference the same
+objects as they did in the parent before the fork.
+If a new process is then to be run using
+.IR execve (2),
+the process would normally inherit these descriptors.  Most
+of the descriptors can be rearranged with
+.IR dup2 (2)
+or deleted with
+.I close
+before the
+.I execve
+is attempted, but if some of these descriptors will still
+be needed if the execve fails, it is necessary to arrange for them
+to be closed if the execve succeeds.
+For this reason, the call ``fcntl(d, F_SETFD, 1)'' is provided
+which arranges that a descriptor will be closed after a successful
+execve; the call ``fcntl(d, F_SETFD, 0)'' restores the default,
+which is to not close the descriptor.
+.SH "RETURN VALUE
+Upon successful completion, a value of 0 is returned.
+Otherwise, a value of \-1 is returned and the global integer variable
+.I errno
+is set to indicate the error.
+.SH ERRORS
+.I Close
+will fail if:
+.TP 15
+[EBADF]
+\fID\fP is not an active descriptor.
 .SH "SEE ALSO"
-creat(2), open(2), pipe(2), exec(2), ioctl(2)
-.SH DIAGNOSTICS
-Zero is returned if a file is closed;
-\-1 is returned for an unknown file descriptor.
-.SH "ASSEMBLER (PDP-11)"
-(close = 6.)
-.br
-(file descriptor in r0)
-.br
-.B sys close
-.PP
-.SH BUGS
-A file cannot be closed while there are pages which have been
-.I vread
-but not referenced.
+accept(2), flock(2), open(2), pipe(2), socket(2), socketpair(2),
+execve(2), fcntl(2)
-- 
2.20.1