minix/lib/libc/compat-43/getdtablesize.3
Lionel Sambuc f14fb60209 Libraries updates and cleanup
* Updating common/lib
 * Updating lib/csu
 * Updating lib/libc
 * Updating libexec/ld.elf_so
 * Corrected test on __minix in featuretest to actually follow the
   meaning of the comment.
 * Cleaned up _REENTRANT-related defintions.
 * Disabled -D_REENTRANT for libfetch
 * Removing some unneeded __NBSD_LIBC defines and tests

Change-Id: Ic1394baef74d11b9f86b312f5ff4bbc3cbf72ce2
2013-01-14 11:36:26 +01:00

70 lines
2.5 KiB
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.\" Copyright (c) 1983, 1991, 1993
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.\" from: @(#)getdtablesize.2 8.1 (Berkeley) 6/4/93
.\" $NetBSD: getdtablesize.3,v 1.14 2012/01/05 07:05:59 yamt Exp $
.\"
.Dd January 5, 2012
.Dt GETDTABLESIZE 3
.Os
.Sh NAME
.Nm getdtablesize
.Nd get descriptor table size
.Sh LIBRARY
.Lb libc
.Sh SYNOPSIS
.In unistd.h
.Ft int
.Fn getdtablesize void
.Sh DESCRIPTION
The
.Nm
function is an equivalent of
.Fn sysconf
with
.Dv _SC_OPEN_MAX .
.Sh SEE ALSO
.Xr close 2 ,
.Xr dup 2 ,
.Xr getrlimit 2 ,
.Xr open 2 ,
.Xr select 2 ,
.Xr sysconf 3
.Sh HISTORY
The
.Fn getdtablesize
function call appeared in
.Bx 4.2 .
.Pp
Historically, each process had a fixed size descriptor table,
which is guaranteed to have at least 20 slots.
The entries in
the descriptor table are numbered with small integers starting at 0.
The call
.Fn getdtablesize
used to return the size of this table.
It doesn't make much sense these days because the size of the table is dynamic.