freebsd man page for getdtablesize

GETDTABLESIZE(2)					      BSD System Calls Manual						  GETDTABLESIZE(2)

NAME
     getdtablesize -- get file descriptor limit

LIBRARY
     Standard C Library (libc, -lc)

SYNOPSIS
     #include <unistd.h>

     int
     getdtablesize(void);

DESCRIPTION
     The getdtablesize() system call returns the maximum number of file descriptors that the current process may open.	The maximum file descrip-
     tor number that the system may assign is the return value minus one.  Existing file descriptor numbers may be higher if the limit was lowered
     after they were opened.

SEE ALSO
     close(2), closefrom(2), dup(2), getrlimit(2), sysconf(2)

HISTORY
     The getdtablesize() system call appeared in 4.2BSD.

BSD
								  April 24, 2013							       BSD