1/*++ 2/* NAME 3/* open_limit 3 4/* SUMMARY 5/* set/get open file limit 6/* SYNOPSIS 7/* #include <iostuff.h> 8/* 9/* int open_limit(int limit) 10/* DESCRIPTION 11/* The \fIopen_limit\fR() routine attempts to change the maximum 12/* number of open files to the specified limit. Specify a null 13/* argument to effect no change. The result is the actual open file 14/* limit for the current process. The number can be smaller or larger 15/* than the requested limit. 16/* DIAGNOSTICS 17/* open_limit() returns -1 in case of problems. The errno 18/* variable gives hints about the nature of the problem. 19/* LICENSE 20/* .ad 21/* .fi 22/* The Secure Mailer license must be distributed with this software. 23/* AUTHOR(S) 24/* Wietse Venema 25/* IBM T.J. Watson Research 26/* P.O. Box 704 27/* Yorktown Heights, NY 10598, USA 28/*--*/ 29 30/* System libraries. */ 31 32#include "sys_defs.h" 33#include <sys/time.h> 34#include <sys/resource.h> 35#include <errno.h> 36 37/* Application-specific. */ 38 39#include "iostuff.h" 40 41 /* 42 * 44BSD compatibility. 43 */ 44#ifndef RLIMIT_NOFILE 45#ifdef RLIMIT_OFILE 46#define RLIMIT_NOFILE RLIMIT_OFILE 47#endif 48#endif 49 50/* open_limit - set/query file descriptor limit */ 51 52int open_limit(int limit) 53{ 54#ifdef RLIMIT_NOFILE 55 struct rlimit rl; 56#endif 57 58 if (limit < 0) { 59 errno = EINVAL; 60 return (-1); 61 } 62#ifdef RLIMIT_NOFILE 63 if (getrlimit(RLIMIT_NOFILE, &rl) < 0) 64 return (-1); 65 if (limit > 0) { 66 if (limit > rl.rlim_max) 67 rl.rlim_cur = rl.rlim_max; 68 else 69 rl.rlim_cur = limit; 70 if (setrlimit(RLIMIT_NOFILE, &rl) < 0) 71 return (-1); 72 } 73 return (rl.rlim_cur); 74#endif 75 76#ifndef RLIMIT_NOFILE 77 return (getdtablesize()); 78#endif 79} 80 81