GETDTABLESIZE(3) BSD Library Functions Manual GETDTABLESIZE(3)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 ALSOclose(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 ta‐
ble 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.
BSD January 5, 2012 BSD