/* [<][>][^][v][top][bottom][index][help] */
1 /*
2 * Copyright (c) 2000, 2001, 2002, 2003, 2004, 2005, 2008
3 * The President and Fellows of Harvard College.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. Neither the name of the University nor the names of its contributors
14 * may be used to endorse or promote products derived from this software
15 * without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE UNIVERSITY AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE UNIVERSITY OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 */
29
30 #ifndef _KERN_LIMITS_H_
31 #define _KERN_LIMITS_H_
32
33 /*
34 * Constants for libc's <limits.h> - system limits.
35 *
36 * The symbols are prefixed with __ here to avoid namespace pollution
37 * in libc. Use <limits.h> (in either userspace or the kernel) to get
38 * the proper names.
39 *
40 * These are Unix-style limits that Unix; you can change them around
41 * or add others as needed or as are appropriate to your system design.
42 * Likewise, the default values provided here are fairly reasonable,
43 * but you can change them around pretty freely.
44 */
45
46
47 /*
48 * Important, both as part of the system call API and for system behavior.
49 */
50
51 /* Longest filename (without directory) not including null terminator */
52 #define __NAME_MAX 255
53
54 /* Longest full path name */
55 #define __PATH_MAX 1024
56
57 /* Max bytes for an exec function */
58 #define __ARG_MAX (64 * 1024)
59
60
61 /*
62 * Important for system behavior, but not a big part of the API.
63 */
64
65 /* Min value for a process ID (that can be assigned to a user process) */
66 #define __PID_MIN 2
67
68 /* Max value for a process ID */
69 #define __PID_MAX 32767
70
71 /* Max bytes for atomic pipe I/O -- see description in the pipe() man page */
72 #define __PIPE_BUF 512
73
74
75 /*
76 * Not so important parts of the API.
77 */
78
79 /* Max number of supplemental group IDs in process credentials */
80 #define __NGROUPS_MAX 32
81
82 /* Max login name size (for setlogin/getlogin), incl. null */
83 #define __LOGIN_NAME_MAX 17
84
85
86 /*
87 * Not very important at all.
88 *
89 * Most modern systems don't have OPEN_MAX at all, and instead go by
90 * whatever limit is set with setrlimit().
91 */
92
93 /* Max open files per process */
94 #define __OPEN_MAX 128
95
96 /* Max number of iovec structures at once for readv/writev/preadv/pwritev */
97 #define __IOV_MAX 1024
98
99
100 #endif /* _KERN_LIMITS_H_ */