HP-UX Reference (11i v3 07/02) - 2 System Calls (vol 5)

getdtablesize(2) getdtablesize(2)

NAME

getdtablesize() - get the size of the per-process ﬁle descriptor table

SYNOPSIS

#include <unistd.h>

int getdtablesize(void);

DESCRIPTION

The getdtablesize()

function returns the maximum number of ﬁle descriptors that can currently be

stored in a process’ ﬁle descriptor table. This maximum number is also known as the soft limit for open

ﬁles, and can be adjusted up to the hard limit by calling

setrlimit() . The entries in the descriptor

table are numbered with small integers starting at 0 (zero).

The

getdtablesize()

function returns the total number of ﬁle descriptors that a process can have

open simultaneously. Each process is limited to a current maximum (soft limit) and a ﬁxed upper bound

(hard limit) of open ﬁle descriptors. This limit is at least 32. The system-deﬁned limits are conﬁgurable.

See the descriptions of the

maxfiles_lim and

maxfiles kernel parameters in maxﬁles_lim(5) and

maxﬁles(5), respectively, for information about changing the system-deﬁned, per-process limit on open ﬁle

descriptors.

RETURN VALUES

The

getdtablesize() function returns the size of the descriptor table (soft limit), and is always suc-

cessful.