getdtablesize(2)
NAME
getdtablesize - get descriptor table size
SYNOPSIS
#include <unistd.h> int getdtablesize(void); Feature Test Macro Requirements for glibc (see feature_test_macros(7)): getdtablesize(): _BSD_SOURCE || _XOPEN_SOURCE >= 500
DESCRIPTION
getdtablesize() returns the maximum number of files a process can have
open, one more than the largest possible value for a file descriptor.
RETURN VALUE
The current limit on the number of open files per process.
ERRORS
On Linux, getdtablesize() can return any of the errors described for
getrlimit(2); see NOTES below.
CONFORMING TO
SVr4, 4.4BSD (the getdtablesize() function first appeared in 4.2BSD). It is not specified in POSIX.1-2001; portable applications should employ sysconf(_SC_OPEN_MAX) instead of this call.
NOTES
getdtablesize() is implemented as a libc library function. The glibc
version calls getrlimit(2) and returns the current RLIMIT_NOFILE limit,
or OPEN_MAX when that fails. The libc4 and libc5 versions return
OPEN_MAX (set to 256 since Linux 0.98.4).
SEE ALSO
close(2), dup(2), getrlimit(2), open(2)
COLOPHON
- This page is part of release 3.25 of the Linux man-pages project. A
description of the project, and information about reporting bugs, can
be found at http://www.kernel.org/doc/man-pages/.