NAME
getdtablesize —
get descriptor table
size
LIBRARY
Standard C Library (libc, -lc)
SYNOPSIS
#include <unistd.h>
int
getdtablesize(
void);
DESCRIPTION
The
getdtablesize function is an equivalent of
sysconf() with
_SC_OPEN_MAX
.
SEE ALSO
close(2),
dup(2),
getrlimit(2),
open(2),
select(2),
sysconf(3)
HISTORY
The
getdtablesize() function call appeared in
4.2BSD.
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
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.