opensolaris man page for getdtablesize

getdtablesize(3C)					   Standard C Library Functions 					 getdtablesize(3C)

NAME
       getdtablesize - get the file descriptor table size

SYNOPSIS
       #include <unistd.h>

       int getdtablesize(void);

DESCRIPTION
       The getdtablesize() function is equivalent to getrlimit(2) with the RLIMIT_NOFILE option.

RETURN VALUES
       The getdtablesize() function returns the current soft limit as if obtained from a call to getrlimit() with the RLIMIT_NOFILE option.

ERRORS
       No errors are defined.

USAGE
       There is no direct relationship between the value returned by getdtablesize() and OPEN_MAX defined in <limits.h>.

       Each  process  has a file 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 getdtablesize() function returns the current maximum size of this table by calling  the  getrlimit()
       function.

SEE ALSO
       close(2), getrlimit(2), open(2), setrlimit(2), select(3C)

SunOS 5.11							    1 Mar 1996							 getdtablesize(3C)