sysconf.c revision 1.1.1.1.4.1
1 /*- 2 * Copyright (c) 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * This code is derived from software contributed to Berkeley by 6 * Sean Eric Fagan of Cygnus Support. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. All advertising materials mentioning features or use of this software 17 * must display the following acknowledgement: 18 * This product includes software developed by the University of 19 * California, Berkeley and its contributors. 20 * 4. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 */ 36 37 #if defined(LIBC_SCCS) && !defined(lint) 38 static char sccsid[] = "@(#)sysconf.c 8.2 (Berkeley) 3/20/94"; 39 #endif /* LIBC_SCCS and not lint */ 40 41 #include "namespace.h" 42 #include <sys/param.h> 43 #include <sys/sysctl.h> 44 #include <sys/time.h> 45 #include <sys/resource.h> 46 47 #include <errno.h> 48 #include <unistd.h> 49 50 /* 51 * sysconf -- 52 * get configurable system variables. 53 * 54 * XXX 55 * POSIX 1003.1 (ISO/IEC 9945-1, 4.8.1.3) states that the variable values 56 * not change during the lifetime of the calling process. This would seem 57 * to require that any change to system limits kill all running processes. 58 * A workaround might be to cache the values when they are first retrieved 59 * and then simply return the cached value on subsequent calls. This is 60 * less useful than returning up-to-date values, however. 61 */ 62 long 63 sysconf(name) 64 int name; 65 { 66 struct clockinfo clk; 67 struct rlimit rl; 68 size_t len; 69 int mib[2], value; 70 71 len = sizeof(value); 72 73 switch (name) { 74 /* 1003.1 */ 75 case _SC_ARG_MAX: 76 mib[0] = CTL_KERN; 77 mib[1] = KERN_ARGMAX; 78 break; 79 case _SC_CHILD_MAX: 80 return (getrlimit(RLIMIT_NPROC, &rl) ? -1 : rl.rlim_cur); 81 case _SC_CLK_TCK: 82 return (CLK_TCK); 83 case _SC_JOB_CONTROL: 84 mib[0] = CTL_KERN; 85 mib[1] = KERN_JOB_CONTROL; 86 goto yesno; 87 case _SC_NGROUPS_MAX: 88 mib[0] = CTL_KERN; 89 mib[1] = KERN_NGROUPS; 90 break; 91 case _SC_OPEN_MAX: 92 return (getrlimit(RLIMIT_NOFILE, &rl) ? -1 : rl.rlim_cur); 93 case _SC_STREAM_MAX: 94 mib[0] = CTL_USER; 95 mib[1] = USER_STREAM_MAX; 96 break; 97 case _SC_TZNAME_MAX: 98 mib[0] = CTL_USER; 99 mib[1] = USER_TZNAME_MAX; 100 break; 101 case _SC_SAVED_IDS: 102 mib[0] = CTL_KERN; 103 mib[1] = KERN_SAVED_IDS; 104 goto yesno; 105 case _SC_VERSION: 106 mib[0] = CTL_KERN; 107 mib[1] = KERN_POSIX1; 108 break; 109 110 /* 1003.2 */ 111 case _SC_BC_BASE_MAX: 112 mib[0] = CTL_USER; 113 mib[1] = USER_BC_BASE_MAX; 114 break; 115 case _SC_BC_DIM_MAX: 116 mib[0] = CTL_USER; 117 mib[1] = USER_BC_DIM_MAX; 118 break; 119 case _SC_BC_SCALE_MAX: 120 mib[0] = CTL_USER; 121 mib[1] = USER_BC_SCALE_MAX; 122 break; 123 case _SC_BC_STRING_MAX: 124 mib[0] = CTL_USER; 125 mib[1] = USER_BC_STRING_MAX; 126 break; 127 case _SC_COLL_WEIGHTS_MAX: 128 mib[0] = CTL_USER; 129 mib[1] = USER_COLL_WEIGHTS_MAX; 130 break; 131 case _SC_EXPR_NEST_MAX: 132 mib[0] = CTL_USER; 133 mib[1] = USER_EXPR_NEST_MAX; 134 break; 135 case _SC_LINE_MAX: 136 mib[0] = CTL_USER; 137 mib[1] = USER_LINE_MAX; 138 break; 139 case _SC_RE_DUP_MAX: 140 mib[0] = CTL_USER; 141 mib[1] = USER_RE_DUP_MAX; 142 break; 143 case _SC_2_VERSION: 144 mib[0] = CTL_USER; 145 mib[1] = USER_POSIX2_VERSION; 146 break; 147 case _SC_2_C_BIND: 148 mib[0] = CTL_USER; 149 mib[1] = USER_POSIX2_C_BIND; 150 goto yesno; 151 case _SC_2_C_DEV: 152 mib[0] = CTL_USER; 153 mib[1] = USER_POSIX2_C_DEV; 154 goto yesno; 155 case _SC_2_CHAR_TERM: 156 mib[0] = CTL_USER; 157 mib[1] = USER_POSIX2_CHAR_TERM; 158 goto yesno; 159 case _SC_2_FORT_DEV: 160 mib[0] = CTL_USER; 161 mib[1] = USER_POSIX2_FORT_DEV; 162 goto yesno; 163 case _SC_2_FORT_RUN: 164 mib[0] = CTL_USER; 165 mib[1] = USER_POSIX2_FORT_RUN; 166 goto yesno; 167 case _SC_2_LOCALEDEF: 168 mib[0] = CTL_USER; 169 mib[1] = USER_POSIX2_LOCALEDEF; 170 goto yesno; 171 case _SC_2_SW_DEV: 172 mib[0] = CTL_USER; 173 mib[1] = USER_POSIX2_SW_DEV; 174 goto yesno; 175 case _SC_2_UPE: 176 mib[0] = CTL_USER; 177 mib[1] = USER_POSIX2_UPE; 178 yesno: if (sysctl(mib, 2, &value, &len, NULL, 0) == -1) 179 return (-1); 180 if (value == 0) 181 return (-1); 182 return (value); 183 break; 184 default: 185 errno = EINVAL; 186 return (-1); 187 } 188 return (sysctl(mib, 2, &value, &len, NULL, 0) == -1 ? -1 : value); 189 } 190
Indexes created Tue Sep 30 20:09:53 GMT 2025